JP6042626B2 - Magnetic permeability variable element and magnetic force control device - Google Patents

Description

  The present invention relates to a magnetic permeability variable element and a magnetic force control device using the magnetic permeability variable element.

  In general, as shown in FIG. 9, the magnetic force is controlled by disposing an electromagnet (coil) in a part of a magnetic circuit made of a soft magnetic material and controlling a current flowing through the coil. In FIG. 9, 100 is a yoke (yoke), 101 is a coil, 102 is a work made of a magnetic material to which a magnetic force is applied, 103 is a flow of magnetic flux, and 104 is an attractive force acting on the work 102. In actual use, for example, a spring (not shown) or the like is attached to the workpiece 102, and the position of the workpiece 102 is determined by the balance between the magnetic force and the force of the spring. Specific applications of magnetic force control include solenoids, relays, motors, actuators, electromagnetic valves, and magnetic heads. Although the coil is inexpensive and convenient, it consumes a large amount of power and size, is inefficient because it generates a large amount of wasted heat, and the influence of heat on peripheral components and the magnetic force control device itself is large.

  There is also an example in which a permanent magnet is used to change the magnetic force by mechanically changing the distance between the permanent magnet and the operating point (for example, the position of the workpiece) or the gap (gap) provided in the magnetic circuit. However, a large force against the magnetic force is necessary. In addition, thermostats that use the fact that the magnetization of soft magnetic materials disappears above the Curie temperature to open and close the contacts by turning on and off the magnetic force are also used, but the temperature change is necessary and the use range is also limited Is done.

Further, in Patent Document 1, the magnetic permeability is changed by controlling the temperature of a soft magnetic material having a low Curie temperature, which is arranged in a magnetic circuit including the permanent magnet, with a small heater, using a permanent magnet as a magnetic force generation source. A magnetic head is disclosed.
In Patent Document 2, a permanent magnet is used as a magnetic force generation source, and a magnetostrictive element placed in a magnetic circuit including the permanent magnet is stressed by a stress applying element or the like to distort the magnetostrictive element, and magnetic characteristics (permeability, magnetic resistance, etc.). ) Is disclosed to control the magnetic flux by changing the above.

JP 63-37810 A JP 2006-304584 A

As described above, a general magnetic force control device using a coil has a problem that power consumption and size are large, efficiency is low, and a thermal influence on peripheral devices and the magnetic force control device itself is large. Further, there is a problem that the coil becomes a source of electromagnetic noise.
A magnetic force that changes the magnetic force by using a permanent magnet to mechanically change the distance between the permanent magnet and the operating point (for example, the position of the workpiece) or the gap (gap) provided in the magnetic circuit. In the control device, there is a problem that a large force to counteract the magnetic force is required, and in the magnetic control device that turns on / off the magnetic force using the fact that the magnetization of the soft magnetic material disappears at the Curie temperature or higher, the range of use is There was a problem that was limited.

In addition, the magnetic head disclosed in Patent Document 1 cannot be used near the Curie temperature, requires electric power for heating, has a problem that power consumption increases and response slows when the shape increases. It was.
Further, the magnetic drive mechanism disclosed in Patent Document 2 requires a large force to distort the magnetostrictive element, and the magnetic permeability change amount (magnetoresistance change amount) obtained by distorting the magnetostrictive element is also small. There was a problem that it was inefficient.

  The present invention has been made in order to solve the above problems, and provides a magnetic permeability variable element capable of realizing a magnetic force control apparatus with low power consumption and low heat generation, and a magnetic force control apparatus using the magnetic permeability variable element. The purpose is to provide.

The magnetic permeability variable element of the present invention comprises a magnetic nanocomposite film in which a large number of magnetic nanoparticles are dispersed in a matrix made of an inorganic semiconductor or an organic semiconductor, and an electric field applying means for applying an electric field to the magnetic nanocomposite film. By applying an electric field to the magnetic nanocomposite film, the interaction between the magnetic nanoparticles is changed to change the magnetic properties of the magnetic nanocomposite film.
Further, in one configuration example of the magnetic permeability variable element of the present invention, the electric field applying means includes an insulating film formed on at least one of the upper surface and the lower surface of the magnetic nanocomposite film, and the insulating film sandwiched between the insulating film. And an electrode film formed on the insulating film so as to face the magnetic nanocomposite film, and an electric field is applied to the magnetic nanocomposite film by applying a voltage to the electrode film.
Moreover , in one structural example of the magnetic permeability variable element of the present invention, the magnetic nanoparticles are single magnetic domains and exhibit superparamagnetism near room temperature.
Moreover, in one structural example of the magnetic permeability variable element of the present invention, the magnetic nanoparticles are made of a material containing at least one of Fe, Co, and Ni.
Additionally, in an example of the magnetic permeability variable element of the present invention, the magnetic nanoparticles, the particle size is 2~20nm der is, the particle surface distance between the magnetic nanoparticles are 0.5 to 5 nm.
Moreover, in one structural example of the magnetic permeability variable element of the present invention, the magnetic nanoparticles have a protective layer formed on the outer periphery thereof.
In addition, one configuration example of the magnetic permeability variable element of the present invention further includes a ground electrode film formed on the surface of the magnetic nanocomposite film opposite to the surface in contact with the insulating film. .
In addition, one configuration example of the magnetic permeability variable element according to the present invention is configured such that two magnetic nanocomposite films adjacent to each other face each other with the magnetic nanocomposite film, the insulating film, and the electrode film as structural units. A plurality of units are stacked, and a ground electrode film is provided between the two magnetic nanocomposite films.

  The magnetic force control device of the present invention includes a permanent magnet, a yoke that forms a magnetic circuit together with the permanent magnet, and one or more magnetic permeability variable elements arranged in the magnetic circuit, and the magnetic permeability variable. The element is arranged in at least one of a parallel arrangement, a series arrangement, and a bridge arrangement with respect to the magnetic circuit.

  According to the present invention, it is possible to realize a magnetic permeability variable element with low power consumption and little heat generation, and it is possible to greatly reduce the thermal influence on peripheral devices. In the present invention, since no coil is used for the magnetic permeability variable element, no electromagnetic noise is generated. Therefore, if the magnetic permeability variable element of the present invention is used, a magnetic force control device that can be easily used in the medical field or the like can be realized. In the present invention, it is difficult to be affected by electromagnetic noise from the outside. Further, in the present invention, unlike the conventional magnetic force control device, no large force is required and no heating is required, so that the range of use of the magnetic force control device can be expanded.

  Moreover, in this invention, the oxidation prevention of a magnetic nanoparticle is realizable by forming a protective layer in the outer peripheral part of a magnetic nanoparticle.

  Also, in the present invention, the effect of controlling magnetic properties can be enhanced by stacking a plurality of structural units with the magnetic nanocomposite film, the insulating film, and the electrode film as structural units.

It is sectional drawing which shows the structure of the magnetic permeability variable element which concerns on the 1st Embodiment of this invention. It is sectional drawing which shows the structure of the magnetic permeability variable element which concerns on the 2nd Embodiment of this invention. It is sectional drawing which shows the structure of the magnetic permeability variable element which concerns on the 3rd Embodiment of this invention. It is a figure which shows the structure of the magnetic force control apparatus which concerns on the 4th Embodiment of this invention. It is a figure which shows the structure of the magnetic force control apparatus which concerns on the 5th Embodiment of this invention. It is a figure which shows the structure of the magnetic force control apparatus which concerns on the 6th Embodiment of this invention. It is a figure which shows the structure of the magnetic force control apparatus which concerns on the 7th Embodiment of this invention. It is a figure which shows the structure of the magnetic force control apparatus which concerns on the 8th Embodiment of this invention. It is a figure which shows the structure of the conventional magnetic force control apparatus.

[Principle of the Invention]
The magnetic permeability variable element of the present invention is a magnetic nanocomposite film in which magnetic nanoparticles are dispersed in a semiconductor matrix (base material) (with an insulating film on at least one of the upper and lower surfaces of the magnetic nanocomposite film). By forming an electrode film and controlling the electric field applied (with voltage application means connected to the electrode film), the density (concentration) of carriers (electrons and holes) that can move in the semiconductor matrix is changed, Magnetic properties such as magnetic permeability (or magnetoresistance, magnetic susceptibility, strength of magnetization) of the magnetic nanocomposite film by changing the strength of the interaction between the magnetic nanoparticles in the magnetic nanocomposite film via carriers. Is something that changes.

  As a semiconductor to be a matrix, there are inorganic substances and organic substances. Examples of the inorganic semiconductor include amorphous silicon, polysilicon, and amorphous oxide. As an organic semiconductor, carriers can be injected by an electric field in a π-conjugated system, and there are high molecular systems and low molecular systems. And derivatives and complexes thereof.

The magnetic nanoparticles may be Fe, Co, Ni alone or a material containing at least one of them, specifically, a compound containing at least one of Fe, Co, Ni (for example, Fe ₃ O ₄ ), It is made of an alloy (for example, FeCo, NiFe). A magnetic nanoparticle is a single magnetic domain and has a particle diameter of 1 to 40 nm (more preferably 2 to 20 nm) that exhibits superparamagnetism near room temperature. Such magnetic nanoparticles are arranged in a substantially uniformly dispersed manner in the matrix at intervals of about 0.1 to 10 nm (more preferably 0.5 to 5 nm).

[Carrier-mediated interaction between magnetic nanoparticles in magnetic nanocomposites]
Hereinafter, the interaction between the magnetic nanoparticles in the magnetic nanocomposite via the carrier will be described. When the matrix (base material) is an inorganic semiconductor, the interaction between magnetic nanoparticles is an indirect exchange interaction (RKKY interaction) that works between adjacent magnetic nanoparticles via carriers (electrons and holes) in the semiconductor. Is due to. That is, the magnetic permeability variable element according to the present invention is an electrode film having an insulating film on at least one of the upper and lower surfaces of a magnetic nanocomposite film in which magnetic nanoparticles exhibiting superparamagnetic properties are dispersed in a semiconductor matrix. By changing the density of carriers (electrons and holes) that can move in the matrix by controlling the electric field applied to the magnetic nanocomposite film by voltage application means connected to the electrode film, the magnetic nanocomposite The strength of indirect exchange interaction (RKKY interaction) via carriers between magnetic nanoparticles in the film is changed to change magnetic properties such as magnetic permeability of the magnetic nanocomposite film. As the carrier density increases, the interaction becomes stronger.

  When a positive voltage is applied to the electrode film, electrons are accumulated in the semiconductor matrix near the insulating film, and when a negative voltage is applied, holes are accumulated. The indirect exchange interaction (RKKY interaction) is generally an interaction between spins mediated by conduction electrons, for example, acting up to a distance of about 5 to 10 nm and inversely proportional to the cube of the distance between particles (surface). To do. In addition, the action of making the spin direction parallel (ferromagnetic) or antiparallel (antiferromagnetic) to the distance between particles (surface) oscillates in a cosine function, and the period of the action is Fermi of conduction electrons. Determined by wave number.

  Therefore, depending on the setting of the distance between magnetic nanoparticles, it can be changed from superparamagnetism to ferromagnetism (high permeability) or from superparamagnetism to antiferromagnetism (low permeability) by increasing the number of carriers. it can. First, it becomes ferromagnetism when the magnetic nanoparticles are close to each other, becomes antiferromagnetic when the magnetic nanoparticles are separated from each other, and becomes ferromagnetic when it is further away from each other, while oscillating like a cosine function. Since the action is attenuated, in order to obtain a large effect, the magnetic nanoparticles contact or approach each other, the electron orbits of the magnetic nanoparticles overlap, and apart from the distance where direct exchange interaction occurs, It is preferable to operate with particle surfaces as close as possible to, for example, about 0.5 to 2 nm.

[Superparamagnetism of magnetic nanoparticles]
Next, superparamagnetism of magnetic nanoparticles will be described. A normal bulk ferromagnet has a multi-domain structure in which a domain wall is formed to reduce magnetostatic energy and is divided into a number of regions called magnetic domains. However, when the size of the magnetic material is about several tens to several hundreds of nm or less. Since the energy for creating the domain wall is larger, the magnetic domain is not divided into a single domain structure. In the single domain structure, the maximum coercive force appears.

Superparamagnetism means that when the diameter of a ferromagnetic particle is set to about several tens of nanometers or less, the magnetic anisotropy energy (K _u V) serving as a barrier to the rotation of magnetization with the magnetization direction of each particle being made constant is thermally oscillated. Since it is smaller than the energy (K _B T) (K _u V <K _B T), it means the property that the magnetization direction is uniform within the particle, but the magnetization direction is different between the particles. Here, K _u is crystal magnetic anisotropy constant, V is the volume, K _B is the Boltzmann constant, T is temperature. Superparamagnetism basically eliminates coercivity and hysteresis of the magnetization curve, the magnitude of magnetization is 4 to 5 orders of magnitude larger than that of paramagnetic material, and the magnetic field required for saturation is small. By using magnetic nanoparticles in a superparamagnetic state, it becomes easy to change magnetic properties such as magnetic permeability of the magnetic nanocomposite film, and the range of change of magnetic properties is also increased.

[Whole interaction between magnetic nanoparticles]
Here, the kind of interaction which acts between magnetic nanoparticles is demonstrated in detail. First, the interaction between magnetic nanoparticles is roughly divided into two. One of them is magnetostatic "dipole-dipole interaction" that acts over a long distance between all magnetic materials having a magnetic moment, not limited to nanostructures. When the matrix is non-magnetic / insulator, the influence of “dipole interaction” becomes large. The other is “direct exchange interaction”, “super exchange interaction”, “indirect exchange interaction (RKKY interaction)”, “double exchange interaction”, which are quantum mechanical interactions peculiar to nanostructures. Etc.

  "Direct exchange interaction" is an action that creates ferromagnetism and antiferromagnetism by aligning the spin direction between atoms by overlapping electrons between adjacent atoms, and its strength is 3 more than "dipole interaction". It is known to be about orders of magnitude larger. “Direct exchange interaction” means that the magnetic nanoparticles are in contact with each other, or the distance between the surfaces of the magnetic nanoparticles is about several times less than the distance between atoms (for example, about 1 nm or less), and the magnetic nanoparticles are magnetic and conductive. This works when separated by a matrix material.

  The “super exchange interaction” is a spin interaction mediated by anions such as oxygen and halogen in an oxide magnetic material, and mainly works antiferromagnetically. According to "super exchange interaction", it is reported that when the angle between ions is 180 degrees, it becomes antiferromagnetic, and when it is 90 degrees, it becomes ferromagnetic. The “indirect exchange interaction (RKKY interaction)” is as described above, and acts when the magnetic nanoparticles are separated by a nonmagnetic / conductive matrix material. The “double exchange interaction” acts by strongly combining electron movement and magnetism.

  In the configuration of the present invention, the influence of “indirect exchange interaction (RKKY interaction)” mainly works to change the magnetic properties, but also includes the influence of “dipole interaction”. The effects of “direct exchange interaction” may be slightly included due to contact between each other. The magnitude of the effect of changing the magnetic characteristics is such that the effect of “direct exchange interaction”> the effect of “indirect exchange interaction (RKKY interaction)” >> the effect of “dipole interaction”. . On the other hand, the distance between the particles on which the effect works is such that the distance at which “direct exchange interaction” works <the distance at which “indirect exchange interaction (RKKY interaction)” works << the distance at which “dipole interaction” works become.

  Therefore, by appropriately setting the distance between the magnetic nanoparticles, the occurrence of “direct exchange interaction” is avoided, and the “indirect exchange interaction (RKKY interaction)” works effectively. In the case of “dipole interaction” acting at a long distance, the distance between the centers of magnetic nanoparticles is an object, and “direct exchange interaction” and “indirect exchange interaction (RKKY interaction) acting at a short distance are considered. In the case of “)”, the distance between the surfaces of the magnetic nanoparticles is considered.

  When the matrix is an organic semiconductor, basically, as in the case of the inorganic semiconductor described above, the electric field applied to the magnetic nanocomposite film is controlled by the voltage application means connected to the electrode film to move in the semiconductor matrix. By changing the density of carriers (electrons and holes) that can be generated, and by changing the strength of the interaction between the magnetic nanoparticles in the magnetic nanocomposite film via the carrier, such as the magnetic permeability of the magnetic nanocomposite film Change the characteristics.

  π-conjugated organic semiconductors include acene-based crystalline low-molecular compounds composed of a large number of benzene rings and polymers in which a π-conjugated system in which double bonds called π-bonds are alternately connected is connected in one dimension. All of them contain highly active electrons called π electrons, and can be doped by methods such as electric field application, chemical treatment, and light irradiation. However, a conductive polymer having a one-dimensional chain generally has a strong interaction between an electron system and a lattice system, and unlike a three-dimensional crystal such as silicon, it is not simply an electron or a hole. A soliton or polaron state with lattice distortion appears (a soliton in a degenerate system such as polyacetylene, and a polaron in a non-degenerate system to which most other conductive polymers are applicable).

  There are three types of electric conduction paths: intramolecular chain, intermolecular chain (hopping conduction), fibril or interparticle (hopping conduction). Within the molecular chain, these solitons and polarons become carriers of electrical conduction. A polaron has +1/2 or −1/2 spin and + or −charge, and when the doping concentration is increased, it may be a bipolaron having no spin or a polaron pair having a spin. Whether it is a bipolaron or a polaron pair is determined by stability including electron correlation. In the present invention, in order to induce a correlation between magnetic nanoparticles and bring the spin close to parallel and induce ferromagnetic properties (or antiferromagnetic properties close to antiparallel), the carriers generate spin. It is necessary to have. However, it is also possible to change the magnetic properties by utilizing the effect that the polaron becomes a bipolaron and the correlation between magnetic nanoparticles is weakened.

  Instead of the magnetic nanocomposite film, a semiconductor element (transition element, rare earth element, etc.) responsible for magnetism is added to the semiconductor, and a part of the constituent elements of the semiconductor is replaced with the magnetic element ((dilute) magnetic semiconductor) However, it is not preferable because the magnetic properties such as magnetic permeability are low and most of them operate only at a low temperature. Further, the method of changing the carrier density of a matrix made of a semiconductor by an electric field is almost the same as the method of changing the carrier density in a general thin film transistor (TFT), but the TFT contains magnetic nanoparticles. Absent.

[First Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing the configuration of the magnetic permeability variable element according to the first embodiment of the present invention.
The magnetic permeability variable element 5 of the present embodiment includes a substrate 1, a magnetic nanocomposite film 2 in which a large number of magnetic nanoparticles are dispersed in a matrix formed on the substrate 1, and a magnetic nanocomposite film 2. The insulating film 3 is formed on the insulating film 3 and the electrode film 4 is formed on the insulating film 3.

  Basically, the horizontal direction or the vertical direction in FIG. 1 is the direction in which the magnetic flux flows, but other directions may be used. Hereinafter, for example, of the end surfaces perpendicular to the electrode film forming surface (upper surface in FIG. 1) of the magnetic permeability variable element 5, the end surface into which the magnetic flux flows (the end surface on the N pole side) is the input end, and the end surface from which the magnetic flux flows (the S pole side) Is called the output end. For example, the left end face of the magnetic permeability variable element 5 in FIG. 1 is an input end, and the right end face is an output end, for example.

The substrate 1 is made of a semiconductor or an insulator such as ceramics, glass, or resin. In the present embodiment, a semiconductor is used as the substrate 1.
As described above, the semiconductor that becomes the matrix of the magnetic nanocomposite film 2 includes inorganic substances and organic substances.

The insulating film 3 is made of a silicon oxide film, a silicon nitride film, alumina, a polymer resin, or the like. The insulating film 3 can be produced by a method such as vacuum deposition, sputtering, plasma CVD (Chemical Vapor Deposition), aerosol deposition, or coating method.
The electrode film 4 is made of aluminum, gold, tantalum, molybdenum, an alloy containing these metals, a conductive polymer, or the like. The electrode film 4 can be produced by a method such as vacuum deposition, sputtering, plasma CVD, or coating method.

  When a voltage is applied to the electrode film 4 by a voltage application means (not shown), the density of carriers (electrons and holes) that can move in the matrix of the magnetic nanocomposite film 2 changes. It is possible to change the strength of the interaction between the nanoparticles through the carrier and to control the magnetic properties such as the magnetic permeability (or magnetoresistance, magnetic susceptibility, and strength of magnetization) of the magnetic nanocomposite film 2. Can do. At this time, the magnetic nanocomposite film 2 is preferably connected to a stable constant potential such as ground. In the present embodiment, the magnetic nanocomposite film 2 is connected to the ground potential via the substrate 1 by grounding the substrate 1 made of a semiconductor.

  Next, a method for manufacturing the magnetic nanocomposite film 2 will be described. First, the case where an inorganic semiconductor matrix is used as the matrix of the magnetic nanocomposite film 2 will be described. As the inorganic semiconductor matrix, amorphous silicon, polysilicon, or amorphous oxide similar to the material used in TFTs, solar cells, etc. can be used. In TFTs and solar cells, these inorganic semiconductors are manufactured by plasma CVD or the like. In order to form the magnetic nanocomposite film 2 by dispersing magnetic nanoparticles in an inorganic semiconductor matrix, the following manufacturing method is used. Is used.

  For example, a magnetic nanoparticle in a matrix by a self-organization method using a colloid using a manufacturing method in which amorphous silicon is produced by applying and baking liquid silicon (silicon ink) based on polysilane on the substrate 1 It is possible to produce a magnetic nanocomposite film 2 in which are uniformly dispersed. It is also possible to include a dopant such as boron or phosphorus in liquid silicon. In addition, liquid nanoparticles based on polysilane (silicon ink) are dispersed with magnetic nanoparticles that have been dispersed and treated by adding a dispersant or surfactant to the surface to prevent aggregation between particles. Thus, by applying and baking liquid silicon on the substrate 1, the magnetic nanocomposite film 2 in which magnetic nanoparticles are uniformly dispersed in the amorphous silicon can be produced.

  Similarly, a method of manufacturing amorphous silicon by applying ink containing silicon particles to the substrate 1 by an inkjet method and applying an ultraviolet laser to harden the ink (see, for example, Japanese Patent Application Publication No. 2010-514585) can also be used. . The ink containing silicon particles is dispersed with magnetic nanoparticles that have been subjected to dispersion treatment by adding a dispersant or surfactant to prevent aggregation between the particles on the surface, and then the ink is ink jetted. A magnetic nanocomposite film 2 in which magnetic nanoparticles are uniformly dispersed in amorphous silicon can be produced by applying the composition to the substrate 1 and solidifying it by applying an ultraviolet laser.

  The magnetic nanoparticles are any of Fe, Co, Ni and compounds containing them, and have a single magnetic domain and a particle size of about 1 to 40 nm (more preferably 2 to 20 nm) exhibiting superparamagnetism near room temperature. In the matrix, they are arranged almost uniformly at intervals of about 0.1 to 10 nm (more preferably 0.5 to 5 nm). In many cases, when the particle size is 2 nm or less, it becomes a paramagnetic substance. On the other hand, when the particle size is increased, the magnetization becomes stronger, but when the particle size is 20 nm or more, it often does not become superparamagnetic at room temperature. Further, in order to reduce the distance between the particle surfaces, it is necessary to considerably increase the particle concentration (volume concentration, mass concentration) in the matrix, so that it is difficult to set the distance between the particle surfaces to about several nm.

  Also, the magnetic nanocomposite film 2 can be produced using a cluster deposition apparatus using a gas flow sputtering method. Specifically, a magnetic nanocomposite film 2 is produced by depositing a cluster of magnetic nanoparticles while embedding it in a different substance (matrix) such as silicon, using an apparatus equipped with two gas flow sputtering sources. can do.

  The gas flow sputtering method is a kind of sputtering method in which discharge is performed in a pipe-type or counter-plate type target electrode, and target atoms generated therein are transferred and deposited on a substrate by argon gas. In the gas flow sputtering method, the pressure in the chamber can be set to about 100 Pa, so that a CVD-like soft process can be realized, a high quality film can be obtained with little damage to the substrate and film, and a reactive gas is supplied. This makes it possible to perform high-speed reactive sputtering. Furthermore, the magnetic nanocomposite film 2 can be similarly produced using a similar plasma / gas condensation cluster deposition apparatus.

  Next, a method for manufacturing the magnetic nanocomposite film 2 when an organic semiconductor matrix is used as the matrix of the magnetic nanocomposite film 2 will be described. Crystalline low molecular weight compounds such as pentacene are extremely poorly soluble in general-purpose solvents, and even if they can be dissolved, it is difficult to control semiconductor precipitation from the solution, and printing flexibility is low. For example, a vacuum deposition process is used. However, the literature “Hiromi Minemawari, Toshikazu Yamada, Hiroyuki Matsui, Jun'ya Tsutsumi, Simon Haas, Ryosuke Chiba, Reiji Kumai and Tatsuo Hasegawa,“ Inkjet printing of single-crystal films ”, Nature, Vol.475, p.364- 367, 21 July 2011 ”is applied to produce a magnetic nanocomposite film 2 in which magnetic nanoparticles are uniformly dispersed in a matrix by a self-organization method using colloids, etc. can do.

  The double shot ink jet printing method is a method for producing a semiconductor single crystal thin film having a flatness at a molecular level, and micro droplets by two kinds of inks: an ink in which an organic semiconductor is dissolved and an ink that promotes crystallization of the organic semiconductor. Are alternately printed on the substrate 1. For example, from two inkjet heads using two types of inks: an organic semiconductor C8-BTBT (dioctylbenzothienobenzothiophene) with excellent solubility, a semiconductor matrix / magnetic nanoparticle ink containing magnetic nanoparticles, and a crystallization ink. Coating on the substrate 1. First, the crystallization ink is applied on the substrate 1 from the first ink jet head, and then the semiconductor matrix / magnetic nanoparticle ink is applied on the crystallization ink from the second head, and applied onto the substrate 1. When a micro mixed droplet is formed, the semiconductor crystal grows and the magnetic nanocomposite film 2 can be formed.

  In addition, the above-mentioned semiconductor matrix / magnetic nanoparticle ink (colloid solution) is obtained by putting an organic semiconductor in a magnetic nanoparticle dispersion in which magnetic nanoparticles are dispersed in a solvent capable of dissolving or swelling the organic semiconductor to be used. What is necessary is just to produce by mixing, stirring, and defoaming a magnetic nanoparticle dispersion liquid and an organic semiconductor. Also, without using a magnetic nanoparticle dispersion, a dispersion treatment or surfactant was added to the surface of an organic semiconductor dissolved or swollen in a solvent to prevent aggregation between particles. A semiconductor matrix / magnetic nanoparticle ink may be produced by putting magnetic nanoparticles and directly kneading and defoaming with various mixers, screws, kneaders, and the like. Further, the magnetic nanoparticles may be mixed with the crystallized ink, or the ink in which the magnetic nanoparticles are dispersed may be separately applied from the third head.

  On the other hand, since many polymers are soluble in solvents, a matrix can be produced at almost room temperature and normal pressure using a coating method or a printing method, and in a matrix by a self-assembly method using a colloid. A magnetic nanocomposite film 2 in which magnetic nanoparticles are uniformly distributed can be produced. For example, a colloidal solution in which magnetic nanoparticles are dispersed in a conductive polymer dissolved or swollen in an organic solvent such as toluene, chloroform, tetrahydrofuran, or dichloromethane is manufactured, and well-known coating, printing, and drying such as spin coating and inkjet It may be formed on the substrate 1 by a technique.

  A colloidal solution in which magnetic nanoparticles are dispersed in a conductive polymer is obtained by placing the conductive polymer in a magnetic nanoparticle dispersion in which the magnetic nanoparticles are dispersed in a solvent capable of dissolving or swelling the conductive polymer. The magnetic nanoparticle dispersion liquid and the conductive polymer may be mixed, stirred, and degassed. Also, without using a magnetic nanoparticle dispersion, a dispersing agent or a surfactant for preventing aggregation between particles is added to the surface of a conductive polymer dissolved or swollen in a solvent to perform a dispersion treatment. A colloidal solution in which magnetic nanoparticles are dispersed in a conductive polymer may be prepared by putting the applied magnetic nanoparticles and directly kneading and defoaming with various mixers, screws, kneaders, or the like.

Furthermore, as in the technique disclosed in Japanese Patent Application Laid-Open No. 2005-139438, a method of doping metal ions into a polymer and forming particles by superheated reduction treatment can be used.
If the magnetic nanoparticles are metal, it is very easy to oxidize. Therefore, it is necessary to prevent the magnetic metal nanoparticles from coming into contact with the atmosphere and moisture as much as possible. It is preferable to perform in an inert gas atmosphere chamber or glove box.

The approximate distance between the particle surfaces can be set as follows. The average inter-particle surface distance h _susp is given by a function of the particle diameter d _p and the particle concentration F (volume concentration, vol.%) When considered geometrically, and the center position of the particles is set to the hexagonal close packed position. Woodcock (Woodcock) proposed in the literature "LV Woodcock, Proceeding of a workshop held at Zentrum fur interdisziplinare Forschung University Bielefield, Nov. 11-13, 1985 Edited by Th. Dorfmuller and G. Williams" The formula (1) is known.

Therefore, the approximate average particle surface distance h _susp can be set by adjusting the particle diameter d _p and the particle concentration F using such an equation. For example, the particle concentration is 4.5 vol. %, The average inter-particle surface distances for particles of 3, 5 and 10 nm are about 2.4, 3.9 and 7.8 nm, respectively.

  Next, a supplementary explanation of magnetic nanoparticles will be given. Magnetic nanoparticles that exhibit soft magnetic properties in the bulk state are preferred, but those that exhibit hard magnetic properties in the bulk state exhibit superparamagnetic properties when the particle size is reduced as described above. It doesn't matter. Soft magnetism is a property in which the hysteresis in the magnetization curve is small, that is, the coercive force is small, and the magnetic permeability and saturation magnetization are large. In short, it is a property that is easily magnetized and easily demagnetized. Used for etc. Soft magnetic materials have low magnetocrystalline anisotropy and magnetostriction. On the other hand, hard magnetism is a property having a large hysteresis, that is, a large coercive force (large crystal magnetic anisotropy) and a large energy (BH) product, and is used for a permanent magnet.

  In addition, it is preferable in terms of magnetic properties that the particle diameter of the magnetic nanoparticles is as uniform and as small as possible. However, when priority is given to increasing the magnetic permeability, mixing of large and small particle diameters may be considered. Large particles have large magnetization, and small particles can fill gaps between large particles to reduce magnetic flux leakage and demagnetizing field. Therefore, the magnetic permeability of the magnetic permeability variable element can be increased. Also, large particles tend to become superparamagnetic because they are dragged by the superparamagnetism of small particles.

  Basically, the magnetic susceptibility of magnetic nanoparticles is proportional to the volume (proportional to the cube of the radius), but the surface area of the nanoparticles is very large compared to the volume. For example, the magnetic nanoparticle surface has a spin disorder (spin canting), so that the magnetization is weakened. Therefore, if the particle size becomes too small, the magnetic properties are deteriorated, so there is an appropriate particle size (for example, about 5 to 10 nm).

  In addition, metal nanoparticles are easily oxidized, and the oxidized portion near the surface (FeO, CoO, NiO, etc.) often becomes antiferromagnetic, so that the strength of magnetization becomes even weaker. In nanoparticles, the ratio of the surface to the volume is very large, so the performance degradation due to surface oxidation appears remarkably. In addition, magnetic interaction occurs between the inside (core) and the surface (shell), affecting the characteristics. For example, unidirectional anisotropy due to exchange anisotropy generated between a ferromagnetic core and an antiferromagnetic shell is known. Limited by magnetic material. Furthermore, in some cases, it may be acceptable, but if the particle surface is oxidized, the magnetic nanoparticles are insulated and the action of the present invention is reduced. Therefore, it is necessary to prevent the oxidation of the magnetic nanoparticles as much as possible. .

  Therefore, it is preferable that a thin protective layer for preventing oxidation is formed on the outer peripheral portion of the magnetic nanoparticles within a range not interfering with the interaction between the magnetic nanoparticles via the carrier. Examples of the material of the protective layer having conductivity necessary for this embodiment include noble metals such as carbon (C) and platinum having high corrosion resistance, and arc discharge method, plasma evaporation method, liquid phase synthesis method, solid phase reduction. It can be manufactured by law. It is also possible to increase the oxidation resistance, corrosion resistance, and durability of the particles themselves by forming an alloy or compound such as Fe, Co, Ni (for example, FePt).

  The production method of magnetic nanoparticles is not the pulverization method used in conventional powders, but a synthesis method in which particles are made up from the atomic and molecular levels. Among them, evaporative condensation method and gas phase reaction method are used. A gas phase method and a liquid phase method such as a chemical precipitation method or a solvent evaporation method are mainly used. Examples of the chemical precipitation method include a colloid method, a uniform precipitation method, an alkoxide method, a hydrothermal synthesis method, and a microemulsion method. As the magnetic nanoparticles, particles having various shapes such as a spherical shape, a rod shape, and a string shape can be used.

The magnetic nanoparticle dispersion liquid is produced by dispersing a surface of the magnetic nanoparticle produced by the above method to which a dispersant or a surfactant for preventing aggregation between particles is added in a solvent. In particular, a magnetic metal nanoparticle dispersion prepared by an active liquid surface continuous vacuum deposition method is preferable because it exhibits very good dispersion performance.
The materials and manufacturing methods of the insulating film 3 and the electrode film 4 are as described above.

  In this embodiment, a small magnetic permeability variable element with low power consumption and little heat generation can be realized, and the thermal influence on peripheral devices can be greatly reduced. In this embodiment, since no coil is used, no electromagnetic noise is generated. Therefore, if the magnetic permeability variable element of the present embodiment is used, a magnetic force control device that can be easily used in the medical field or the like can be realized. Further, in this embodiment, it is difficult to be affected by external electromagnetic noise. Moreover, in this Embodiment, since the big force and the heating are not required like the conventional magnetic force control apparatus, the use range of a magnetic force control apparatus can be expanded.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. FIG. 2 is a cross-sectional view showing the configuration of the magnetic permeability variable element according to the second embodiment of the present invention.
The magnetic permeability variable element 5a of the present embodiment includes a substrate 10, an insulating film 11 formed on the substrate 10, an electrode film 12 formed on the insulating film 11, and a magnetic film formed on the electrode film 12. The nanocomposite film 13, the insulating film 14 formed on the magnetic nanocomposite film 13, and the electrode film 15 formed on the insulating film 14 are configured.

The magnetic permeability variable element 5a of the present embodiment corresponds to a configuration in which an insulating film and an electrode film are inserted between the substrate and the magnetic nanocomposite film in the first embodiment. As described in the first embodiment, the horizontal direction or the vertical direction in FIG. 2 is basically the direction in which the magnetic flux flows, but other directions may be used. If the direction in which the magnetic flux flows is a horizontal direction, for example, the left end face of the magnetic permeability variable element 5a becomes an input end, and for example, the right end face becomes an output end.
The substrate 10 is made of a semiconductor or an insulator such as ceramics, glass, or resin. In the present embodiment, a semiconductor is used as the substrate 10. When the substrate 10 made of an insulator is used, the insulating film 11 is not necessary.

  The insulating films 11 and 14 can be manufactured by the same material and manufacturing method as the insulating film 3. The electrode films 12 and 15 can be produced by the same material and manufacturing method as the electrode film 4. The magnetic nanocomposite film 13 can be produced by the same material and manufacturing method as the magnetic nanocomposite film 2.

In the present embodiment, the lower electrode film 12 may be grounded as a ground electrode, and a voltage may be applied to the upper electrode film 15 by a voltage applying means (not shown). Since the operation of the magnetic permeability variable element 5a is the same as that of the first embodiment, description thereof is omitted.
Thus, also in this embodiment, the same effect as that of the first embodiment can be obtained.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. FIG. 3 is a cross-sectional view showing a configuration of a magnetic permeability variable element according to the third embodiment of the present invention.
The magnetic permeability variable element 5b of the present embodiment includes a substrate 20, an insulating film 21 formed on the substrate 20, an electrode film 22 formed on the insulating film 21, and an insulating film formed on the electrode film 22. A film 23; a magnetic nanocomposite film 24 formed on the insulating film 23; an electrode film 25 formed on the magnetic nanocomposite film 24; a magnetic nanocomposite film 26 formed on the electrode film 25; The insulating film 27 is formed on the nanocomposite film 26 and the electrode film 28 is formed on the insulating film 27.

  As described in the first embodiment, the horizontal direction or the vertical direction in FIG. 3 is basically the direction in which the magnetic flux flows, but other directions may be used. If the direction in which the magnetic flux flows is a horizontal direction, for example, the left end face of the magnetic permeability variable element 5b becomes an input end, and for example, the right end face becomes an output end.

The board | substrate 20 consists of insulators, such as a semiconductor or ceramics, glass, resin. In the present embodiment, a semiconductor is used as the substrate 20. In the case where the substrate 20 made of an insulator is used, the insulating film 21 is not necessary.
The insulating films 21, 23, and 27 can be manufactured using the same material and manufacturing method as the insulating film 3. The electrode films 22, 25, 28 can be produced by the same material and manufacturing method as the electrode film 4. The magnetic nanocomposite films 24 and 26 can be produced by the same material and manufacturing method as the magnetic nanocomposite film 2.

  In the present embodiment, the electrode film 25 may be grounded as a ground electrode, and a voltage may be applied to the electrode films 22 and 28 by voltage application means (not shown). The same voltage may be applied to the electrode films 22 and 28. When a voltage is applied to the electrode films 22 and 28 by a voltage application means (not shown), the density of carriers (electrons and holes) that can move in the matrix of the magnetic nanocomposite films 24 and 26 changes. It is possible to change the strength of the interaction between the magnetic nanoparticles in the magnetic nanoparticles 24 and 26 via the carrier, and the magnetic permeability of the magnetic nanocomposite films 24 and 26 (or magnetic resistance, magnetic susceptibility, and strength of magnetization). Etc. can be controlled.

The only region in the magnetic nanocomposite film where carriers are concentrated and the interaction between magnetic nanoparticles works strongly is the thin layer near the electrode film. For this reason, when the magnetic permeability variable element is laminated as in the present embodiment, the effect of controlling the magnetic characteristics can be enhanced.
In the present embodiment, the magnetic nanocomposite film has two layers, but three or more layers may be stacked. In this case, the magnetic nanocomposite film, the insulating film, and the electrode film are used as structural units, and a plurality of structural units are stacked such that two adjacent magnetic nanocomposite films face each other. A ground electrode film may be provided on the substrate.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. FIG. 4 is a diagram showing a configuration of a magnetic force control apparatus according to the fourth embodiment of the present invention. The magnetic force control device includes a permanent magnet (hard magnetic material) 30, yokes (yokes) 31-1, 31-2, and 31-5 made of a soft magnetic material such as permalloy or an electromagnetic steel plate, and a magnetic permeability variable element 5. Consists of In FIG. 4, 32 is an air gap provided between the yokes 31-1 and 31-2, 33 is a work made of a magnetic material, 34 is a flow of magnetic flux, and 35 is an attractive force acting on the work 33. Further, “N” in FIG. 4 indicates the N pole of the permanent magnet 30, and “S” indicates the S pole. In this embodiment, a magnetic permeability variable element 5 is arranged in series with respect to a magnetic circuit composed of a permanent magnet 30 and yokes 31-1, 31-2 and 31-5.

The yoke 31-5 serves as a bypass for flowing a magnetic flux when the magnetic permeability of the magnetic permeability variable element 5 becomes low. The yoke 31-5 is not an essential component, but when the yoke 31-5 is not provided, leakage of magnetic flux into the air becomes large.
Further, since the magnetic force is drastically reduced when the air gap 32 is large, the actual air gap 32 should be as small as possible.

  The yoke 31-1 and the magnetic permeability variable element 5 are joined by an adhesive that is relatively flexible and can absorb stress, such as an epoxy adhesive. In terms of magnetic characteristics, it is preferable to join the magnetic permeability variable element 5 and the yoke 31-1 so as not to open the gap. In addition, in order to apply a voltage to the magnetic permeability variable element 5, it is necessary to electrically insulate between the magnetic permeability variable element 5 and the yoke 31-1.

  When a voltage V is applied between the electrode film 4 and the substrate 1 by a voltage application means (not shown), carriers (electrons and holes) that can move in the matrix of the magnetic nanocomposite film 2 of the magnetic permeability variable element 5 as described above. ) Changes, the strength of the interaction between the magnetic nanoparticles in the magnetic nanocomposite film 2 via the carrier can be changed, and the magnetic permeability (or magnetoresistance, magnetic susceptibility, magnetization strength) can be changed. And the like can be controlled. At this time, in a state where the fluctuation frequency of the applied voltage is low and close to a steady state, the current flowing through the magnetic permeability variable element 5 is almost zero.

  In the present embodiment, a magnetic force control device with low power consumption and low heat generation can be realized, and the thermal influence on peripheral devices can be greatly reduced. In this embodiment, since no coil is used, electromagnetic noise is not generated, and a magnetic force control device that can be easily used in the medical field or the like can be realized. Further, in this embodiment, it is difficult to be affected by external electromagnetic noise. Moreover, in this Embodiment, since the big force and the heating are not required like the conventional magnetic force control apparatus, the use range of a magnetic force control apparatus can be expanded.

  In the example of FIG. 4, the magnetic permeability variable element 5 is arranged so that the film thickness direction (the vertical direction in FIG. 1) of the magnetic permeability variable element 5 and the direction of the magnetic flux flow 34 are orthogonal to each other. The magnetic permeability variable element 5 may be arranged so that the film thickness direction of the variable element 5 and the direction of the magnetic flux flow 34 are parallel to each other.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described. FIG. 5 is a diagram showing the configuration of the magnetic force control apparatus according to the fifth embodiment of the present invention. The same components as those in FIG. 4 are denoted by the same reference numerals. In the present embodiment, the magnetic permeability variable element 5 is arranged in parallel to the magnetic circuit composed of the permanent magnet 30 and the yokes 31-1 and 31-2. That is, the input end of the magnetic permeability variable element 5 is connected to the yoke 31-1 connected to the N pole of the permanent magnet 30, and the yoke 31-2 connected to the S pole of the permanent magnet 30. The output end of the magnetic permeability variable element 5 is connected. Since other configurations are the same as those of the fourth embodiment, detailed description thereof is omitted. According to the present embodiment, the same effect as in the fourth embodiment can be obtained.

  In the example of FIG. 5, the magnetic permeability variable element 5 is arranged so that the film thickness direction (the vertical direction in FIG. 1) of the magnetic permeability variable element 5 and the direction of the flow 34 of magnetic flux flowing into the magnetic permeability variable element 5 are orthogonal to each other. However, as described in the fourth embodiment, the magnetic permeability variable element 5 so that the film thickness direction of the magnetic permeability variable element 5 and the direction of the flow of magnetic flux 34 flowing into the magnetic permeability variable element 5 are parallel to each other. May be arranged.

[Sixth Embodiment]
Next, a sixth embodiment of the present invention will be described. FIG. 6 is a diagram showing the configuration of the magnetic force control apparatus according to the sixth embodiment of the present invention. The same components as those in FIG. In the present embodiment, the magnetic permeability variable element 5-1 is arranged in series with the magnetic circuit as in the fourth embodiment, and the magnetic permeability variable element 5-2 in the same manner as in the fifth embodiment. Are arranged in parallel to the magnetic circuit. Since other configurations are the same as those of the fourth and fifth embodiments, detailed description thereof is omitted. According to the present embodiment, in addition to the same effects as in the fourth embodiment, the magnetic permeability variable elements 5-1 and 5-2 having substantially the same characteristics are arranged in series and in parallel in the magnetic circuit. Further, it is possible to correct error factors such as temperature characteristics, and to obtain an effect that the control range can be increased.

[Seventh Embodiment]
Next, a seventh embodiment of the present invention will be described. FIG. 7 is a diagram showing the configuration of the magnetic force control apparatus according to the seventh embodiment of the present invention. The same components as those in FIG. 4 are denoted by the same reference numerals. In the present embodiment, four magnetic permeability variable elements 5-1, 5-2, 5-3 and 5-4 are arranged in a bridge shape. That is, the input end of the magnetic permeability variable element 5-1 and the input end of the magnetic permeability variable element 5-2 are connected to the yoke 31-1, and the output terminal of the magnetic permeability variable element 5-3 and the magnetic permeability variable element 5 are connected. -4 is connected to the yoke 31-2, the yoke 31-3 between the output terminal of the magnetic permeability variable element 5-1 and the input terminal of the magnetic permeability variable element 5-3, and the magnetic permeability variable element 5 The air gap 32 is formed between the output end of -2 and the yoke 31-4 between the input end of the magnetic permeability variable element 5-4.

In the present embodiment, the voltage applied to the magnetic permeability variable elements 5-1 to 5-4 is adjusted to change the magnetic permeability of the magnetic permeability variable elements 5-1 and 5-4 to the magnetic permeability variable elements 5-2 and 5. −3, the magnetic flux flows from the yoke 31-3 to the yoke 31-4. On the other hand, when the magnetic permeability of the magnetic permeability variable elements 5-2 and 5-3 is made larger than the magnetic permeability of the magnetic permeability variable elements 5-1 and 5-4, the magnetic flux moves in the direction from the yoke 31-4 to the yoke 31-3. Flowing.
Thus, in the present embodiment, the direction of the magnetic flux in the air gap 32 (operating point) can be freely reversed.

[Eighth Embodiment]
Next, an eighth embodiment of the present invention will be described. FIG. 8 is a diagram showing the configuration of the magnetic force control apparatus according to the eighth embodiment of the present invention. The same components as those in FIG. 4 are denoted by the same reference numerals. In this embodiment, two sets of the configuration of the magnetic force control device of FIG. 5 described in the fifth embodiment are used, and the polarities of the permanent magnets 30 are reversed, and the air gap 32 (operating point) is set. Two sets of magnetic force control devices are combined so as to be common. That is, the input end of the magnetic permeability variable element 5-1 and the magnetic permeability variable element 5-2 with respect to the yoke 31-1 connected to the N pole of the permanent magnet 30-1 and the S pole of the permanent magnet 30-2. And the output end of the magnetic permeability variable element 5-1 with respect to the yoke 31-2 connected to the S pole of the permanent magnet 30-1 and the N pole of the permanent magnet 30-2. The input end of the magnetic permeability variable element 5-2 is connected, the yoke 31-1 between the input end of the magnetic permeability variable element 5-1 and the output end of the magnetic permeability variable element 5-2, and the magnetic permeability variable element 5-1. An air gap 32 is formed between the output end of the first and the yoke 31-2 between the input end of the magnetic permeability variable element 5-2.

In the present embodiment, the voltage applied to the magnetic permeability variable elements 5-1 and 5-2 is adjusted so that the magnetic permeability of the magnetic permeability variable element 5-1 is larger than the magnetic permeability of the magnetic permeability variable element 5-2. Then, the magnetic flux in the air gap 32 (operating point) flows from the yoke 31-2 to the yoke 31-1. On the other hand, when the magnetic permeability of the magnetic permeability variable element 5-2 is made larger than the magnetic permeability of the magnetic permeability variable element 5-1, the magnetic flux in the air gap 32 (operating point) moves from the yoke 31-1 to the yoke 31-2. Flowing.
Thus, in the present embodiment, the direction of the magnetic flux in the air gap 32 (operating point) can be freely reversed.

  In the fourth to eighth embodiments, the magnetic permeability variable element 5 described in the first embodiment is used. However, instead of the magnetic permeability variable element 5, the second and third embodiments will be described. Needless to say, the magnetic permeability variable elements 5a and 5b may be used. In this case, the magnetic permeability variable elements 5a and 5b are arranged such that the film thickness direction of the magnetic permeability variable elements 5a and 5b (the vertical direction in FIGS. 2 and 3) and the flow direction of the magnetic flux flowing into the magnetic permeability variable elements 5a and 5b are orthogonal to each other. The magnetic permeability variable elements 5a and 5b are arranged so that the film thickness direction of the magnetic permeability variable elements 5a and 5b is parallel to the flow direction of the magnetic flux flowing into the magnetic permeability variable elements 5a and 5b. May be. In order to apply a voltage to the magnetic permeability variable elements 5a and 5b, it is necessary to electrically insulate between the magnetic permeability variable elements 5a and 5b and the yoke.

  The present invention can be applied to a technique for controlling magnetic permeability and a technique for controlling magnetic force.

  DESCRIPTION OF SYMBOLS 1,10,20 ... Board | substrate, 2,13,24,26 ... Magnetic nanocomposite film | membrane, 3,11,14,21,23,27 ... Insulating film, 4,12,15,22,25,28 ... Electrode film | membrane 5, 5-1 to 5-4, 5a, 5b ... variable permeability element, 30, 30-1, 30-2 ... permanent magnet, 31-1 to 31-5 ... yoke, 32 ... air gap, 33 ... Workpiece, 34 ... magnetic flux flow, 35 ... attractive force.

Claims (9)

A magnetic nanocomposite film in which a number of magnetic nanoparticles are dispersed in a matrix made of an inorganic or organic semiconductor;
It comprises an electric field applying means for applying an electric field to this magnetic nanocomposite film,
A magnetic permeability variable element, wherein an electric field is applied to the magnetic nanocomposite film to change the magnetic properties of the magnetic nanocomposite film by changing the interaction between the magnetic nanoparticles. In the magnetic permeability variable element according to claim 1,
The electric field applying means includes
An insulating film formed on at least one of the upper and lower surfaces of the magnetic nanocomposite film;
An electrode film formed on the insulating film so as to face the magnetic nanocomposite film across the insulating film;
A magnetic permeability variable element, wherein an electric field is applied to the magnetic nanocomposite film by applying a voltage to the electrode film. In the magnetic permeability variable element according to claim 1 or 2,
The magnetic nanoparticle has a single magnetic domain and exhibits superparamagnetism near room temperature. The magnetic permeability variable element according to any one of claims 1 to 3,
The magnetic nanoparticle is made of a material containing at least one of Fe, Co, and Ni. The magnetic permeability variable element according to any one of claims 1 to 4,
The magnetic nanoparticle has a particle size of 2 to 20 nm, and a distance between particle surfaces of the magnetic nanoparticles is 0.5 to 5 nm. The magnetic permeability variable element according to any one of claims 1 to 5,
The magnetic nanoparticle is a magnetic permeability variable element, wherein a protective layer is formed on an outer periphery of the magnetic nanoparticle. The magnetic permeability variable element according to claim 2 ,
The magnetic permeability variable element further comprising a ground electrode film formed on the surface of the magnetic nanocomposite film opposite to the surface in contact with the insulating film. The magnetic permeability variable element according to claim 2 ,
Using the magnetic nanocomposite film, the insulating film, and the electrode film as structural units, a plurality of the structural units are stacked such that two adjacent magnetic nanocomposite films face each other, A magnetic permeability variable element, wherein a ground electrode film is provided. With permanent magnets,
A yoke that forms a magnetic circuit with the permanent magnet;
At least one or a plurality of magnetic permeability variable elements according to any one of claims 1 to 8 disposed in the magnetic circuit,
The magnetic permeability control device, wherein the magnetic permeability variable element is arranged in at least one of a parallel arrangement, a serial arrangement, and a bridge type arrangement with respect to the magnetic circuit.

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