JP2017152959A - Metamaterial device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metamaterial device which operates over wider bands than the prior arts while avoiding a conductor loss and is isotropic in a three-dimensional manner.SOLUTION: A unit cell 10 comprises: a dielectric resonator 1 in a center of the unit cell 10; multiple strip dielectrics 3 surrounding the dielectric resonator 1; and a host medium 2 supporting the dielectric resonator 1 and the strip dielectrics 3. In the unit cell 10, the multiple strip dielectrics 3 include: first strip dielectrics that are disposed in a first direction; second strip dielectrics that are disposed in a second direction; and third strip dielectrics that are disposed in a third direction. The first strip dielectrics are disposed in parallel with each other and cyclically, the second strip dielectrics are disposed in parallel with each other and cyclically, and the third strip dielectrics are disposed in parallel with each other and cyclically. The dielectric resonator 1 has a dielectric constant that is higher than a dielectric constant of the host medium 2, and the strip dielectric 3 has a dielectric constant that is equal to or higher than the dielectric constant of the dielectric resonator 1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a metamaterial device which is an electromagnetic artificial structure exhibiting a negative refractive index.

  The metamaterial device is composed of a plurality of unit components (hereinafter referred to as unit cells) having a sub-wavelength size. A characteristic behavior of the metamaterial device is that a structure having a negative refractive index that causes backward propagation of electromagnetic waves can be configured. A negative refractive index is realized when the effective permittivity and effective permeability of the structure are simultaneously negative.

  In general, the unit cell of a metamaterial device is anisotropic, and the behavior of the metamaterial device varies greatly depending on the propagation direction and polarization direction of electromagnetic waves. It is not easy to design a metamaterial device structure that is isotropic, that is, has no direction dependency, with respect to electromagnetic waves propagating in three independent directions or electromagnetic waves having different polarization characteristics.

  Several three-dimensional metamaterial devices that have a negative refractive index with respect to electromagnetic waves propagating in three independent directions have already been proposed (see, for example, Patent Documents 1 to 7). Furthermore, as an isotropic three-dimensional metamaterial device that exhibits a negative refractive index independent of the propagation direction and polarization direction of electromagnetic waves, a group of dielectric particles having an electromagnetic field distribution similar to a magnetic dipole, and alternating current There has been proposed a composite structure composed of a combination with a metal fine wire grating having a shielding effect against an electric field. In this structure, the dielectric particle group is used as a structure exhibiting a negative magnetic permeability. A resonance mode is used in which vortices of electric lines of force are formed in the dielectric particles so that each dielectric particle exhibits an electromagnetic field distribution similar to a magnetic dipole. On the other hand, the metal fine wire lattice is used as a structure exhibiting a negative dielectric constant. The metal fine wire lattice exhibits a negative dielectric constant when an electromagnetic wave having a wavelength longer than twice the interval is incident on a pair of metal fine wires arranged at a predetermined interval. When a single metal wire grid is used, a cut-off region where electromagnetic waves cannot propagate appears and shows a shielding effect.

Japanese Patent Laid-Open No. 2006-114489 JP 2008-244683 A JP 2008-252293 A JP 2009-272592 A JP 2013-005044 A Japanese Patent No. 558526 International Publication No. 2013/133175

  In general, a metamaterial device operates in principle not only in the microwave region but also in the millimeter wave region or the terahertz wave region by changing the size of its constituent elements. However, in a composite structure composed of dielectric particles and fine metal wire lattices, the influence of conductor loss increases as the operating band increases. In addition, the metal thin wire has a problem that the electrical conductivity is lowered due to a change with time, which affects the characteristics of the metamaterial device.

  As one of the methods for avoiding the influence due to the conductor loss, a method for configuring a metamaterial device made of only a dielectric has already been proposed. However, many of them have a structure in which dielectric columns, well known as photonic crystals, are periodically arranged on a two-dimensional lattice, and polarization dependency occurs due to the two-dimensional structure. As a three-dimensional isotropic structure, a method using two kinds of dielectric particle groups forming an electric dipole and a magnetic dipole has been proposed. When a negative dielectric constant is realized, an electric dipole is used. Since a higher-order resonance mode similar to the child is used, there is a problem that the operating band is extremely narrow, and the negative dielectric constant disappears even with a manufacturing variation of several percent or less.

  The object of the present invention is to solve the above-mentioned problems and to operate in a wider band than before, while avoiding conductor loss, is extremely small in change over time, and is easy to manufacture. It is to provide a metamaterial apparatus.

According to the metamaterial device according to the first aspect of the present invention,
In a metamaterial device including a plurality of unit cells arranged periodically,
Each of the unit cells includes a dielectric resonator disposed in the center of the unit cell, a plurality of strip dielectrics disposed so as to surround the dielectric resonator, the dielectric resonator, and the strip dielectric. A host medium that supports the body,
In each of the unit cells, the plurality of strip dielectrics include at least one first strip dielectric disposed in a first direction and at least a second direction disposed in a second direction different from the first direction. One second strip dielectric and at least one third strip dielectric disposed in a third direction having a predetermined angle with respect to a plane stretched by the first and second directions;
In the metamaterial device configured by periodically arranging the plurality of unit cells, the first strip dielectrics are periodically and parallel to each other, and the second strip dielectrics are parallel to each other. And the third strip dielectrics are arranged in parallel and periodically with each other,
The dielectric resonator has a dielectric constant higher than that of the host medium, and the strip dielectric has a dielectric constant equal to or higher than that of the dielectric resonator.

According to the metamaterial device according to the second aspect of the present invention, in the metamaterial device according to the first aspect,
The shape and size of the unit cell and the shape of the dielectric resonator so that the effective permittivity and effective permeability of the metamaterial device are both negative with respect to an electromagnetic wave having a predetermined frequency incident on the metamaterial device. , Dimensions, and relative dielectric constant, thickness of the strip dielectric, spacing between the first, second, and third strip dielectrics periodically, and relative dielectric constant of the host medium are set. It is characterized by that.

According to the metamaterial device according to the third aspect of the present invention, in the metamaterial device according to the second aspect,
Each unit cell includes a waveguide formed by the plurality of strip dielectrics, each unit cell has a predetermined cutoff frequency, and each unit cell is incident on the metamaterial device. The effective dielectric constant of the metamaterial device is configured to be negative with respect to electromagnetic waves having a frequency lower than the off-frequency,
The dielectric resonator is excited by an electromagnetic wave having a predetermined frequency incident on the dielectric resonator in a resonance form having an electromagnetic field distribution similar to a magnetic dipole moment, and the metamaterial device effectively transmits the electromagnetic wave. The magnetic susceptibility is configured to be negative.

According to the metamaterial device according to the fourth aspect of the present invention, in the metamaterial device according to one of the first to third aspects,
Each of the unit cells is a cube, and the first, second, and third directions are orthogonal to each other.

According to the metamaterial device according to the fifth aspect of the present invention, in the metamaterial device according to one of the first to fourth aspects,
The dielectric resonator has a spherical shape.

According to the metamaterial device according to the sixth aspect of the present invention, in the metamaterial device according to one of the first to fourth aspects,
The dielectric resonator has a cylindrical shape or a polygonal column shape.

According to the metamaterial device according to the seventh aspect of the present invention, in the metamaterial device according to one of the first to fourth aspects,
The dielectric resonator has a cubic shape, a polyhedron shape, or a rhombohedral shape.

According to the metamaterial device according to the eighth aspect of the present invention, in the metamaterial device according to one of the first to seventh aspects,
Each of all combinations of two unit cells adjacent to each other on one surface among the plurality of unit cells shares the strip dielectric on the one surface.

According to the metamaterial device according to the ninth aspect of the present invention, in the metamaterial device according to one of the first to eighth aspects,
The host medium comprises a first substrate having a cavity and a second substrate sandwiching the first substrate, and the first strip dielectric is provided on the first substrate and / or the second substrate. And / or a second strip dielectric is formed,
The dielectric resonator is disposed in the cavity of the first substrate and formed in a unit form sandwiched between the second substrates, or formed in a state where two or more layers of the unit form are laminated. It has the said 3rd strip dielectric material, It is characterized by the above-mentioned.

  According to the present invention, there is provided a three-dimensional isotropic metamaterial device that can operate in a wider band than the prior art while avoiding a conductor loss, has a very small change with time, and is easy to manufacture. be able to.

It is a perspective view which shows the structure of the unit cell 10 of the metamaterial apparatus 20 which concerns on embodiment of this invention. It is a perspective view which shows the one-dimensional metamaterial apparatus 20 which consists of the unit cell 10 of FIG. It is a perspective view which shows the two-dimensional metamaterial apparatus 30 which consists of the unit cell 10 of FIG. It is a perspective view which shows the three-dimensional metamaterial apparatus 40 which consists of the unit cell 10 of FIG. It is sectional drawing of the horizontal direction which passes along the center of the unit cell 10 of FIG. It is a perspective view which shows the structure of unit cell 10A of the metamaterial apparatus which concerns on the 1st modification of embodiment of this invention. It is a perspective view which shows the structure of the unit cell 10B of the metamaterial apparatus which concerns on the 2nd modification of embodiment of this invention. It is a top view which shows the structure of unit cell 10C of the metamaterial apparatus which concerns on the 3rd modification of embodiment of this invention. It is a disassembled perspective view for demonstrating the manufacturing method of 40 A of 3D metamaterial apparatuses which concern on embodiment of this invention. It is a perspective view which shows the structure of the board | substrate layer 101 of FIG. It is sectional drawing in the A-A 'line of FIG. It is a perspective view which shows the structure of the board | substrate layer 102 of FIG. It is sectional drawing in the B-B 'line of FIG. It is sectional drawing which shows the structure of 40 A of 3D metamaterial apparatuses containing the board | substrate layer 101-1, 102-1, 101-2, 102-2, 101-3 of FIG. It is a graph which shows the reflection coefficient S11 and the passage coefficient S21 of the transmission line which consists only of a conductor grating of the one-dimensional metamaterial apparatus which concerns on a comparative example. It is a graph which shows the reflection coefficient S11 and the passage coefficient S21 of the transmission line which consists only of a dielectric grating of the one-dimensional metamaterial apparatus which concerns on the Example of this invention. It is a figure for demonstrating the propagation direction of the electromagnetic waves in a metamaterial apparatus. It is a graph which shows the dispersion | distribution curve of the three-dimensional metamaterial apparatus which concerns on a comparative example. It is a graph which shows the dispersion | distribution curve of the three-dimensional metamaterial apparatus which concerns on the Example of this invention. It is a graph which shows the reflection coefficient S11 and the passage coefficient S21 of the transmission line of the three-dimensional metamaterial apparatus which concerns on the Example of this invention.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. Reference is made to xyz coordinates in the drawing. In addition, in each following embodiment, the same code | symbol is attached | subjected about the same component.

  FIG. 1 is a perspective view showing a structure of a unit cell 10 of a metamaterial device 20 according to an embodiment of the present invention. The unit cell 10 includes a dielectric resonator 1 disposed in the center of the unit cell 10 and a plurality of strip dielectrics 3xa to 3xd, 3ya to 3yd, 3za to 3zd disposed so as to surround the dielectric resonator 1. (Hereinafter collectively referred to as “3”) and a host medium 2 that supports the dielectric resonator 1 and the strip dielectric 3. The host medium 2 is a dielectric that fills the space in the unit cell 10, for example. The host medium 2 may be an organic material such as epoxy or polyimide, or may be a mixture of an organic material and glass fiber.

  The unit cell 10 may be a parallelepiped shape such as a rectangular parallelepiped, but is preferably a cube having a side length p in consideration of three-dimensional isotropic property and ease of manufacture.

  The dielectric resonator 1 has a relative dielectric constant much higher than that of the host medium 2. For example, when the host medium 2 has a relative dielectric constant of 1 to 10, the dielectric resonator 1 has a relative dielectric constant of 15 to 150. The dielectric resonator 1 is, for example, a cube having a side length l. The center of the dielectric resonator 1 may substantially coincide with the center of the unit cell 10.

  The strip dielectric 3 has a dielectric constant substantially equal to or higher than that of the dielectric resonator 1. For example, when the dielectric resonator 1 has a relative dielectric constant of 15 to 150, the strip dielectric 3 has a relative dielectric constant of 50 to 2000.

  The plurality of strip dielectrics 3 are provided on each side of the unit cell 10. The strip dielectric 3 includes strip dielectrics 3xa to 3xd disposed along the x direction, strip dielectrics 3ya to 3yd disposed along the y direction, and strip dielectrics 3za disposed along the z direction. ~ 3zd. In a metamaterial device configured by periodically arranging a plurality of unit cells 10 one-dimensionally, two-dimensionally or three-dimensionally, a plurality of x-direction strip dielectrics are parallel to each other and periodically And a plurality of y-direction strip dielectrics are also arranged in parallel and periodically with each other, and a plurality of z-direction strip dielectrics are also arranged in parallel and periodically with each other. For example, strip dielectrics (such as 3za-3zd) disposed along the z direction are periodically disposed in the x direction, periodically disposed in the y direction, and further in other directions (eg, the strip dielectric 3za). And a direction along a plane including 3zd, etc.) are also periodically arranged for each predetermined length.

  FIG. 2 is a perspective view showing a one-dimensional metamaterial device 20 including the unit cell 10 of FIG. FIG. 3 is a perspective view showing a two-dimensional metamaterial device 30 including the unit cell 10 of FIG. FIG. 4 is a perspective view showing a three-dimensional metamaterial device 40 including the unit cell 10 of FIG. The plurality of unit cells 10 are periodically arranged one-dimensionally, two-dimensionally or three-dimensionally. At this time, some of the plurality of strip dielectrics 3 are periodically and parallel to each other along the x-axis, and other parts of the plurality of strip dielectrics 3 are parallel to each other along the y-axis. The other portions of the plurality of strip dielectrics 3 are arranged in parallel and periodically with each other along the z-axis. When the unit cell 10 and the dielectric resonator 1 are cubic and the plurality of strip dielectrics 3 are formed as described above, the metamaterial devices 20, 30, and 40 in which such unit cells are periodically arranged. Becomes isotropic.

  The one-dimensional metamaterial device 20 can be used as a transmission line having ports P1 and P2 at both ends, for example. In this case, dielectric blocks 21 and 22 are provided at ports P1 and P2 for impedance matching with the space. Similarly, the two-dimensional metamaterial device 30 and the three-dimensional metamaterial device 40 can also be used as transmission lines having ports and dielectric blocks at both ends.

  The metamaterial device including the unit cell 10 operates in a frequency band such as a microwave band, a millimeter wave band, and a terahertz frequency band, for example. The metamaterial device including the unit cell 10 may operate in a frequency band of several MHz, may operate in a frequency band of several GHz, or may operate in a frequency band of several THz, for example, in consideration of the size. It may work.

  Next, the operation principle of the metamaterial device including the unit cell 10 in FIG. 1 will be described.

  As will be described below, the metamaterial device including the unit cell 10 inserts the dielectric resonator 1 having a negative effective magnetic permeability into the unit cell 10 having a negative effective dielectric constant to thereby obtain the effective dielectric. The rate and effective permeability are both negative with respect to an electromagnetic wave having a predetermined frequency.

  In order to realize a negative dielectric constant, for example, Patent Document 7 uses a lattice structure made of strip conductors. On the other hand, the metamaterial device according to the embodiment of the present invention includes a lattice structure made of a strip dielectric made of a dielectric material having a high dielectric constant, instead of the conventional lattice structure made of a strip conductor. The conductor material has high conductivity and the impedance becomes almost zero, but the dielectric material having a very high dielectric constant becomes almost zero in the high frequency band, and such a replacement is possible.

  When an electromagnetic wave having a parallel electric field component is incident on a structure composed of two conductor plates or rods that are parallel to each other, when the wavelength of the electromagnetic wave is longer than twice the distance between the conductor plates or the rods, the structure The effective dielectric constant of the object becomes negative. Therefore, the structure exhibits a shielding effect, and a cut-off region (band gap) where electromagnetic waves cannot propagate appears. When an electromagnetic wave having a parallel electric field component is incident on a similar structure made of a dielectric instead of a conductor, a shielding effect is exhibited in a specific operating frequency band as in the case of a conductor, and a cutoff region (band Gap) appears. The major difference between the lattice structure composed of strip conductors and the lattice structure composed of strip dielectrics is that the former shows frequency characteristics of low-frequency rejection, while the latter shows frequency characteristics of band-rejection, and the high frequency of the stopband. The electromagnetic wave can be propagated not only on the side but also on the low frequency side. Especially on the low frequency side, the electromagnetic characteristics of the lattice structure made of strip dielectric and the surrounding host medium 2 are coarse-grained (smoothed), and electromagnetic waves can be propagated as a dielectric medium having a finite positive dielectric constant. It becomes.

  FIG. 5 is a cross-sectional view in the horizontal direction (direction along a plane parallel to the xy plane) passing through the center of the unit cell 10 in FIG. In FIG. 5, the center unit cell 10 and a part of unit cell adjacent to it are shown. Each of the strip dielectrics 3 (only the strip dielectrics 3za to 3zd in the z direction are shown in FIG. 5) has, for example, a square cross-sectional shape having a side length L2. The strip dielectrics 3za to 3zd are periodically arranged with an interval L1 in the x direction and periodically arranged with an interval L3 in the y direction. However, as described above, when the unit cell 10 is a cube, L1 = L3. The unit cell 10 is a waveguide in which, for example, in the x direction, sections of length L2 surrounded by the strip dielectric 3 and sections of length L1 not surrounded by the strip dielectric 3 are alternately arranged. Configured as The effective dielectric constant of the section surrounded by the strip dielectric 3 in this waveguide becomes negative in a frequency region lower than the cutoff frequency of the TE mode. Therefore, this waveguide is an electromagnetic wave having a frequency lower than the cut-off frequency. For example, when an electromagnetic wave directed in the + x direction arrives as an incident wave, the negative effective dielectric constant ε2 in the section surrounded by the strip dielectric 3 A section having <0 and not surrounded by the strip dielectric 3 is configured to have a positive effective dielectric constant ε1> 0. At this time, the metamaterial device as a whole has an effective dielectric constant of a predetermined value of positive, zero, or negative. Similarly, the unit cell 10 is configured as a waveguide in which sections surrounded by the strip dielectric 3 and sections not surrounded by the strip dielectric 3 are alternately arranged along the y direction and the z direction. The These waveguides are electromagnetic waves having a frequency lower than the cut-off frequency, and when an electromagnetic wave directed in the y direction or the z direction arrives as an incident wave, the negative effective dielectric constant in the section surrounded by the strip dielectric 3 And is configured to have a positive effective dielectric constant in a section not surrounded by the strip dielectric 3. Even at these times, the metamaterial device as a whole has an effective dielectric constant of a predetermined value of positive, zero, or negative.

  Each unit cell 10 has a cut-off frequency (effective value of the entire unit cell 10) that depends on the entire structure of the unit cell 10 including the waveguide formed by the plurality of strip dielectrics 3 and other portions. Cut-off frequency). The metamaterial device including the unit cell 10 has a negative effective dielectric constant when an electromagnetic wave having a frequency lower than the cutoff frequency is incident, and is zero or positive when an electromagnetic wave having a frequency higher than the cutoff frequency is incident. The effective dielectric constant is

  Furthermore, the dielectric resonator 1 has a resonance form with an electromagnetic field distribution similar to the magnetic dipole moment. Here, “an electromagnetic field distribution similar to the magnetic dipole moment” means that a concentric vortex with closed lines of electric force is formed in a plane perpendicular to a certain axis in the dielectric resonator 1. In addition, the magnetic field lines are directed substantially along the axis in the vicinity of the center of the dielectric resonator 1, and the magnetic field lines extend outside the dielectric resonator 1 to form a closed curve. Say. In general, the magnetic field lines are sorenoidal (always closed), and in this case, the magnetic field lines have a distribution that spreads widely outside the dielectric resonator 1. While more electric energy is stored inside the dielectric resonator 1 than magnetic energy, the energy stored by the magnetic field is larger than the energy stored by the electric field outside the dielectric resonator 1. Thus, the coupling between the dielectric resonator 1 and the external electromagnetic field is dominated by magnetic coupling.

  In order to change the effective permeability of the dielectric resonator 1, when an electromagnetic wave having a predetermined frequency enters the dielectric resonator 1, the magnetic field vector of the electromagnetic wave is similar to the magnetic dipole moment in the dielectric resonator 1. It is necessary to excite the resonance state of the electromagnetic field distribution. As a result, a positive, zero, or negative effective permeability is realized in the unit cell 10 according to the frequency of the electromagnetic wave. At this time, the metamaterial device composed of the unit cells 10 as a whole has an effective magnetic permeability of a predetermined value of positive, zero, or negative.

  The shape and size of the unit cell 10 and the shape and size of the dielectric resonator 1 are set so that the effective permittivity and effective permeability of the metamaterial device including the unit cell 10 are both negative with respect to the electromagnetic wave having a predetermined frequency. The relative dielectric constant, the thickness of the strip dielectric 3, the interval at which the strip dielectric 3 is periodically arranged, and the relative dielectric constant of the host medium 2 are determined. At this time, the metamaterial device including the unit cell 10 is configured as a metamaterial device having an isotropic propagation characteristic indicating a negative refractive index without depending on the propagation direction and the polarization direction of the electromagnetic wave.

  In order to obtain a negative refractive index, it is necessary to simultaneously make the dielectric constant and the magnetic permeability negative. However, the negative magnetic permeability band formed in the upper band of the resonance frequency of the dielectric resonator 1 and the strip dielectric By designing such that the band gap of the negative dielectric constant band gap formed by the lattice structure made of the body 3 overlaps, a metamaterial device having a negative refractive index can be configured.

  In order for the metamaterial device composed of the unit cells 10 to have isotropic propagation characteristics, among the resonance modes of the dielectric resonator 1 having an electromagnetic field distribution similar to the magnetic dipole moment, the axis of symmetry in the x direction is used. The first resonance form having the second resonance form having a symmetry axis in the y direction and the third resonance form having a symmetry axis in the z direction all have substantially the same resonance frequency (that is, different from each other). It is necessary to substantially degenerate the three resonance modes. When an electromagnetic wave having a frequency near the resonance frequency is incident on the dielectric resonator 1, the dielectric resonator 1 is in a resonance state or a state having an electromagnetic field distribution close to that regardless of the propagation direction of the electromagnetic wave. In addition, the electromagnetic field distribution inside and outside the dielectric resonator 1 at the time of resonance is expressed as one of the three substantially degenerated resonance modes or a combination (linear sum) according to the component of the propagation direction vector of the electromagnetic wave. The

  According to the metamaterial device according to the embodiment of the present invention, by providing a lattice structure made of the strip dielectric 3 in place of the lattice structure made of the strip conductor, conductor loss caused by high frequency or change with time is reduced. Thus, it is possible to provide a three-dimensional isotropic metamaterial device that can operate in a wider band than conventional ones.

  Furthermore, since the metamaterial device according to the embodiment of the present invention has a simple structure, it can be easily and inexpensively manufactured.

  Furthermore, since the metamaterial device according to the embodiment of the present invention does not include metal conductor parts, it can operate stably over a long period of time without causing a change over time due to oxidation or the like.

  A metamaterial device having an arbitrary shape having a negative refractive index can be configured simply by periodically arranging the plurality of unit cells 10.

  Although a cubic unit cell 10 is shown in FIG. 1, the shape of the unit cell is not limited to a cube. If a metamaterial device can be configured by periodically arranging a plurality of unit cells in a one-dimensional, two-dimensional, or three-dimensional manner, an arbitrary shape such as a rectangular parallelepiped, a prism (such as a hexagonal column), or a regular tetrahedron A unit cell having a shape or a combination of a plurality of types of unit cells can be used. In each unit cell, the plurality of strip dielectrics are arranged along at least three directions. That is, in each unit cell, the plurality of strip dielectrics are at least one first strip dielectric disposed in the first direction and at least one disposed in a second direction different from the first direction. Two second strip dielectrics and at least one third strip dielectric disposed in a third direction having a predetermined angle with respect to a plane stretched by the first and second directions. In a three-dimensional metamaterial apparatus configured by periodically arranging a plurality of unit cells in three dimensions, the first strip dielectrics are arranged in parallel and periodically with each other, and the second strip dielectric is Parallel to each other and periodically disposed, the third strip dielectrics are disposed parallel to each other and periodically. In the metamaterial device configured as described above, it is possible to easily realize isotropic propagation characteristics that do not depend on the propagation direction and polarization direction of electromagnetic waves. However, for isotropic propagation characteristics, the unit cell preferably has a symmetric shape such as a cube rather than a shape such as a rectangular parallelepiped whose dimensions and the like differ depending on the direction.

  The dielectric resonator 1 may be composed of a single dielectric material or may be composed of a combination of a plurality of dielectric materials. For example, the dielectric resonator 1 may be one obtained by firing a dielectric ceramic or one obtained by molding a dielectric ceramic powder. If a material with a dielectric loss as small as possible is used, a metamaterial device with a small propagation loss can be realized.

  The dielectric resonator 1 may or may not be in contact with the dielectric resonator 1 of the unit cell 10 adjacent to the unit cell 10 including the dielectric resonator 1.

  The host medium 2 is, for example, a dielectric having a relative dielectric constant much lower than that of the dielectric resonator 1, for example, a dielectric such as an organic material having a relative dielectric constant of 1/10 to 1/5. It is configured by filling the unit cell 10 with a body. Further, as the host medium 2, at least a part of the inside of the unit cell 10 may be filled with air, or the inside of the unit cell 10 may be filled with a combination of air and a dielectric, or a combination of a plurality of dielectrics. It may be filled.

  Whereas a normal medium has a positive effective permittivity and a positive effective permeability (right-handed medium), the metamaterial device has a left-handed medium having a negative effective permittivity and a negative effective permeability. There is something that works. The metamaterial device according to the embodiment includes a right-handed metamaterial device, a left-handed metamaterial device, a single negative metamaterial device in which one of dielectric constant and permeability is negative and the other is positive, depending on the operating frequency, effective dielectric It may be configured as a right / left-handed composite metamaterial device that operates as a metamaterial device with zero rate or permeability.

  In addition, the frequency at which the effective permittivity of the metamaterial device is zero is generally different from the frequency at which the effective permeability is zero. However, by matching these frequencies, the metamaterial device according to the embodiment can be balanced right-handed / It may be configured as a left-handed composite metamaterial device. The frequency at which the effective dielectric constant and effective permeability of the right / left-handed composite metamaterial device have zero values is generally different. In that case, in the band between the frequency at which the effective dielectric constant becomes zero and the frequency at which the effective magnetic permeability becomes zero, only one of the effective dielectric constant and the effective magnetic permeability has a negative value, and the other Has a positive value. In this band, the electromagnetic wave propagation condition is not satisfied and the electromagnetic wave cannot be propagated. The right-hand / left-hand composite metamaterial device operates as a left-handed metamaterial device because both the effective permittivity and effective permeability are negative in the lower band of this forbidden band, and both have positive values in the upper band. Operates as a right-handed metamaterial device. When the effective permittivity and the frequency at which the effective magnetic permeability are equal, no forbidden band is formed, and the left-handed transmission band and the right-handed transmission band are continuously connected. Such a metamaterial device is referred to as a balanced right-hand / left-handed composite metamaterial device, and another device is referred to as a non-equilibrium right-hand / left-handed composite metamaterial device. The balanced right-hand / left-handed composite metamaterial device does not produce a forbidden band, and the group velocity does not become zero even at a frequency where the phase constant becomes zero, and efficient power transmission is possible.

  FIG. 6 is a perspective view showing the structure of the unit cell 10A of the metamaterial device according to the first modification of the embodiment of the present invention. The unit cell 10A includes a dielectric resonator 1A having a spherical shape with a radius R1. In the case of the spherical dielectric resonator 1A, the magnetic wall (the tangential component of the magnetic field is zero) at the boundary under the condition that the dielectric constant of the dielectric resonator 1A is sufficiently larger than the dielectric constant of the host medium 2. Assuming that, the resonance mode is approximately calculated. In this simplified model, the electromagnetic field distribution of the dielectric resonator 1A is expressed as a TE011 resonance mode.

  FIG. 7 is a perspective view showing the structure of the unit cell 10B of the metamaterial device according to the second modification of the embodiment of the present invention. The unit cell 10B of FIG. 7 includes a cylindrical dielectric resonator 1B having a radius R2 and a height H1. In the case of the cylindrical dielectric resonator 1B, (1) an electromagnetic field distribution similar to a magnetic dipole moment parallel to the axis of symmetry of the cylinder is formed in the vicinity of the TE01δ resonance mode and its resonance frequency, and (2) HE11δ resonance. In the vicinity of the mode and its resonance frequency, an electromagnetic field distribution similar to the magnetic dipole moment is formed in the direction perpendicular to the side surface of the cylinder. In this case, since the degree of freedom in determining the direction perpendicular to the side surface of the cylinder is 2, it is assumed here that the two resonance states are degenerated. When the resonance frequencies of (1) and (2) are the same, an electromagnetic field distribution similar to three magnetic dipole moments having symmetric axes in three different directions can be realized at the same frequency. . The diameter (radius R2 × 2) and height H1 of the dielectric resonator 1B are determined to be approximately the same length so that the resonance frequencies of the TE01δ mode and the HE11δ mode of the dielectric resonator 1B are degenerated at substantially the same frequency.

  Also in the metamaterial device including the unit cell 10A of FIG. 6 or the unit cell 10B of FIG. 7, it is possible to easily realize isotropic propagation characteristics that do not depend on the propagation direction and polarization direction of electromagnetic waves.

  The dielectric resonator may have a shape other than a cube, a sphere, and a cylinder, for example, an arbitrary shape such as a spheroid, a polygonal column, a polyhedron, a rhombohedron, or a combination of a plurality of types of shapes. You may have. However, when attention is paid to one unit cell, isotropic propagation characteristics are impaired when a dielectric resonator having an asymmetric shape is used. Even when such a dielectric resonator is used, on average, isotropic propagation characteristics are realized by arranging the dielectric resonators in various directions in a plurality of unit cells. be able to. Further, when paying attention to one unit cell, isotropic propagation characteristics are impaired unless the dielectric resonator is arranged at the center of the unit cell. Even if the dielectric resonator is not arranged in the center of the unit cell, the isotropic propagation characteristics can be achieved on average by arranging the dielectric resonator in various different positions in the unit cells. can do.

  FIG. 8 is a plan view showing the structure of the unit cell 10C of the metamaterial device according to the third modification of the embodiment of the present invention. The unit cells may be formed individually, or may be formed as a single unit with adjacent unit cells. In the latter case, each of all combinations of two unit cells that are adjacent to each other on one plane among the plurality of unit cells (that is, any two unit cells that are adjacent to each other on one plane) The strip dielectric 3 may be shared in the plane. Referring to FIG. 8, unit cell 10 </ b> C shares strip dielectric 3 with adjacent unit cells on each side. According to the configuration of FIG. 8, by sharing the strip dielectric 3 between two adjacent unit cells, a plurality of unit cells can be formed together and the manufacture of the metamaterial device can be simplified.

  FIG. 8 shows an example in which a plurality of unit cells are two-dimensionally arranged. Similarly, when a plurality of unit cells are arranged one-dimensionally or three-dimensionally, a plurality of unit cells are formed together. May be.

  Next, an example of a method for manufacturing a metamaterial device according to an embodiment of the present invention will be described with reference to FIGS.

  FIG. 9 is an exploded perspective view for explaining a method of manufacturing the three-dimensional metamaterial device 40A according to the embodiment of the present invention. The three-dimensional metamaterial device 40A includes a plurality of stacked substrate layers 101-1, 102-1, 101-2, 102-2, 101-3, ..., 101-N. As will be described later, some of the substrate layers 102-1, 102-2,..., 102- (N-1) (hereinafter collectively referred to as “102”) accommodate the dielectric resonator 1A. The remaining substrate layers 101-1, 101-2, 101-3,..., 101-N (hereinafter collectively referred to by reference numeral “101”) are disposed between the substrate layers 102, respectively. The dielectric resonator 1 </ b> A is fixed to the cavity of the substrate layer 102. 2 is formed by sputtering or the like on at least one surface of each of the substrate layers 101 and 102, or is formed in a through hole penetrating each of the substrate layers 101 and 102. The number of substrate layers 101 and 102 can be arbitrarily selected in consideration of necessary characteristics. The three-dimensional metamaterial device 40A shown in FIG. 9 includes N substrate layers 101 and N−1 substrate layers 102.

  FIG. 10 is a perspective view showing the structure of the substrate layer 101 of FIG. FIG. 11 is a cross-sectional view taken along the line A-A ′ of FIG. 10. The base material of the substrate layer 101 is formed of a dielectric substrate 111 made of a semi-cured resin such as epoxy mixed with epoxy, polyimide, or glass fiber, and at least one surface of the dielectric substrate 111 (FIGS. 10 and 11). In this case, a plurality of linear dielectric patterns 112x (corresponding to the strip dielectrics 3xa to 3xd in the x direction in FIG. 1) extending along the x direction and the y direction extend along the + z side surface. A lattice-like dielectric film made of a plurality of existing linear dielectric patterns 112y (corresponding to the strip dielectrics 3ya to 3yd in the y direction in FIG. 1) is patterned. Further, through holes 113 penetrating the dielectric substrate 111 are formed by using a laser method or a punching method at positions (lattice points) where the linear dielectric patterns 112x and 112y intersect each other. As will be described later, the through-hole 113 is provided with a dielectric rod 131 (corresponding to the strip dielectrics 3za to 3zd in the z direction in FIG. 1).

  FIG. 12 is a perspective view showing the structure of the substrate layer 102 of FIG. 13 is a cross-sectional view taken along line B-B ′ of FIG. The base material of the substrate layer 102 is formed of a dielectric substrate 121 made of a semi-cured resin such as epoxy mixed with epoxy, polyimide, or glass fiber, and at least one surface of the dielectric substrate 121 (FIGS. 11 and 12). In this case, a plurality of linear dielectric patterns 122x (corresponding to the strip dielectrics 3xa to 3xd in the x direction in FIG. 1) extending in the x direction and the y direction extend in the + z side surface. A lattice-like dielectric film made of a plurality of existing linear dielectric patterns 122y (corresponding to the strip dielectrics 3ya to 3yd in the y direction in FIG. 1) is patterned. Further, through holes 123 penetrating the dielectric substrate 121 are formed at positions (lattice points) where the linear dielectric patterns 122x and 122y intersect using a laser method or a punching method, respectively. As will be described later, the through-hole 123 is provided with a dielectric rod 131 (corresponding to the strip dielectrics 3za to 3zd in the z direction in FIG. 1). Further, in each region surrounded by the linear dielectric patterns 122x and 122y on the dielectric substrate 121, a cavity 124 penetrating the dielectric substrate 121 is formed by using a laser method or a punching method. In each of the cavities 124, the dielectric resonators 1A are provided.

  A through hole 123 and a hole of a cavity 124 are formed in the dielectric substrate 121 of the substrate layer 102. The diameter of the through hole 123 is formed smaller than the diameter of the dielectric resonator 1A, and the hole of the cavity 124 is formed larger than the diameter of the dielectric resonator 1A. Therefore, if a plurality of dielectric resonators 1A (which is sufficiently larger than the number of cavities 124 in a certain substrate layer 102) are arranged on the dielectric substrate 121 and the dielectric resonator 1A is swept with a squeegee, the dielectric resonators 1A can be loaded into the cavity 124. At this time, since the diameter of the through hole 123 is smaller than that of the cavity 124, the dielectric resonator 1 </ b> A does not enter the through hole 123. In the case where the diameter of the through hole 123 is larger than the cavity 124, the dielectric resonator 1A can be formed in the same manner by using a suction method device used when installing a solder ball on a circuit board in LSI mounting. Only the cavity 124 can be loaded.

  FIG. 14 is a cross-sectional view showing the structure of a three-dimensional metamaterial device 40A including the substrate layers 101-1, 102-1, 101-2, 102-2, and 101-3 of FIG. After the dielectric resonator 1A is loaded into the cavities 124 of the substrate layers 102-1, 102-2, the positions of the through holes 113, 123 are aligned and the substrate layers 101-1, 102-1, 101, as shown in FIG. -2, 102-2, 101-3 are stacked and the whole is compressed in the z direction. Since the substrate layers 101 and 102 are in a semi-cured state as described above, they are integrated as a whole by compression. Next, by inserting a dielectric rod 131 (corresponding to the strip dielectrics 3za to 3zd in the z direction in FIG. 1) into the through holes 113 and 123 and applying heat of about 80 to 180 ° C. to the whole, Finally cures. According to this example of the manufacturing method, each dielectric resonator 1A includes the linear dielectric patterns 112x and 112y of the substrate layer 101 and the substrate layer 102, similarly to being surrounded by the strip dielectric 3 of FIG. The linear dielectric patterns 122x and 122y and the dielectric rod 131 are surrounded. Each dielectric resonator 1A, linear dielectric patterns 112x, 112y, 122x, 122y, and dielectric rod 131 are supported by dielectric substrates 111, 121. Therefore, according to this example of the manufacturing method, as in the metamaterial device 40 of FIG. 4, a three-dimensional meta-structure constructed by periodically arranging a plurality of unit cells each including the dielectric resonator 1A. The material device 40A can be manufactured.

  9 to 14 show the spherical dielectric resonator 1A, other dielectric resonators (cubes, rectangular parallelepipeds, cylinders, etc.) may be used instead.

  A one-dimensional metamaterial device as shown in FIG. 2 may be formed using the method for manufacturing a metamaterial device described with reference to FIGS. 9 to 14, and a two-dimensional metamaterial device as shown in FIG. 3 is formed. May be.

  Next, simulation results of the metamaterial device according to the embodiment described above will be described with reference to FIGS.

For calculation of electromagnetic wave propagation, a commercially available high-frequency electromagnetic simulator based on the finite element method was used. The structural parameters used for the calculation are shown below. The unit cell 10 is a cube, the length of one side thereof is p = 10.3 mm, the dielectric resonator 1 is also a cube, and the length of one side thereof is l _DR = 6 mm. The thickness of the strip dielectric 3 was w = 0.8 mm. The relative permittivity of the dielectric resonator 1 is ε _DR = 104, the relative permittivity of the host medium 2 is ε _H = 2.2, and the relative permittivity of the strip dielectric 3 is ε _L = 600. .

  First, in order to confirm a frequency band showing a negative dielectric constant generated by the lattice structure made of the strip dielectric 3, a unit cell not including the dielectric resonator 1 but including only the host medium 2 and the strip dielectric 3 is used. The resulting three-dimensional metamaterial device (see FIG. 2) was analyzed. In this simulation, five unit cells in the traveling direction of electromagnetic waves and an infinite number of unit cells in the lateral direction are periodically arranged three-dimensionally. The dielectric blocks 21 and 22 in FIG. 2 for impedance matching are not provided at both ends of the three-dimensional metamaterial device, and free space is provided. As an input signal, a TEM mode electromagnetic wave was vertically incident.

  FIG. 15 is a graph showing a reflection coefficient S11 and a transmission coefficient S21 of a transmission line composed only of a conductor grid of a three-dimensional metamaterial device according to a comparative example. In the case of FIG. 15, each unit cell does not have the dielectric resonator 1, is provided with the host medium 2, and is further provided with a lattice structure including a strip conductor instead of the strip dielectric 3. According to FIG. 15, it can be seen that the cut-off frequency is about 10 GHz, and all signals input at a lower frequency are cut off. From FIG. 15, the metamaterial device that generates a negative dielectric constant using a lattice structure made of a conductor exhibits a low-frequency blocking characteristic.

  FIG. 16 is a graph showing a reflection coefficient S11 and a transmission coefficient S21 of a transmission line composed only of a dielectric grating of the three-dimensional metamaterial device according to the embodiment of the present invention. In the case of FIG. 16, each unit cell is set not to include the dielectric resonator 1 but to include only the host medium 2 and the strip dielectric 3. Since electromagnetic waves penetrate inside the lattice structure made of the strip dielectric 3, this corresponds to a case where the size of the lattice is larger than that of the lattice structure made of the strip conductor. According to FIG. 16, it can be seen that the cut-off frequency slightly decreases and exists around 8 GHz. The electromagnetic wave incident from one of the ports P1 and P2 has its electric field attenuated exponentially and is cut off in the middle of the transmission line. Further, according to FIG. 16, in the case of the lattice structure made of the strip dielectric 3, it can be seen that a pass band appears even in a lower band of 3 GHz or less. From FIG. 16, the metamaterial device that generates a negative dielectric constant using the lattice structure made of the strip dielectric 3 exhibits not a low-frequency band stop but a band stop characteristic. In fact, in addition to the lattice structure composed of the strip dielectric 3, the dielectric resonator 1 having a high dielectric constant is inserted into the unit cell 10 in order to manipulate the effective permeability, so that the effective dielectric constant of the metamaterial device is To rise. Therefore, in the metamaterial device according to the embodiment of the present invention, it is necessary to consider at the time of designing that the cut-off frequency is further lowered than the above.

  FIG. 17 is a diagram for explaining the propagation direction of the electromagnetic wave in the metamaterial device. FIG. 17 represents a representation of a wavenumber region related to the three-dimensional metamaterial device. In the wave number domain (spatial frequency domain) obtained by Fourier transforming the spatial coordinates (x, y, z), each point is represented by a wave vector β = (βx, βy, βz) having components βx, βy, βz. . Further, when the structure of the three-dimensional metamaterial device has periodicity, the dispersion curve representing the propagation characteristics has periodicity in the wavenumber region, and the entire region is obtained using a partial region in the wavenumber region called the first Brillouin region. Expressed. The origin (βx, βy, βz) = (0, 0, 0) of this wave number region is called “Γ” point. When the electromagnetic wave propagates along the x-axis in FIG. 15, the wave vector has only a βx component, and the boundary point (π / L, 0, 0) of the Brillouin region in that direction is represented by “X”. Similarly, when the electromagnetic wave propagates in the (x, y, z) = (1, 1, 0) direction in FIG. 15, the components of the wave vector have a relationship of βx = βy and βz = 0, The boundary point (π / L, π / L, 0) of the Brillouin region is represented as “M”. Further, when the electromagnetic wave propagates in the (x, y, z) = (1, 1, 1) direction of FIG. 15, the components of the wave vector have a relationship of βx = βy = βz, and the Brillouin region in that direction The boundary points (π / L, π / L, π / L) are represented as “R”.

  FIG. 18 is a graph showing a dispersion curve of the three-dimensional metamaterial device according to the comparative example. FIG. 18 shows a dispersion curve of the three-dimensional metamaterial device when the unit cell 10 of FIG. 1 includes a strip conductor instead of the strip dielectric 3. The dispersion curve in FIG. 18 shows an eigenmode solution obtained by imposing a periodic boundary condition on the unit cell 10B in FIG. In FIG. 19, “ΓX” indicates a dispersion curve when the electromagnetic wave propagates from the origin to the point (1, 0, 0) (+ x direction) in the xyz coordinates of FIG. 15, and “ΓM” indicates the point from the origin. A dispersion curve when propagating to (1, 1, 0) is shown, and “ΓR” shows a dispersion curve when propagating from the origin to the point (1, 1, 1). When the propagation direction of the electromagnetic wave is “ΓX”, the propagation characteristic does not depend on the polarization direction. When the propagation direction of the electromagnetic wave was “ΓM”, a dispersion curve of horizontal polarization (polarization direction parallel to the xy plane) and a dispersion curve of vertical polarization (polarization direction perpendicular to the xy plane) were obtained. When the propagation direction of the electromagnetic wave is “ΓR”, the propagation characteristic does not depend on the polarization direction. The dispersion curve in FIG. 18 was obtained from the eigenvalue calculation. β represents the phase constant of the three-dimensional metamaterial device. Note that the phase constant β corresponds to a component of the wave vector β. As can be seen from FIG. 18, the dispersion characteristic is isotropic near the Γ point.

  FIG. 19 is a graph showing a dispersion curve of the three-dimensional metamaterial device according to the example of the present invention. In either case, it propagates with a negative refractive index from 4.1 GHz to 4.35 GHz (left-handed mode), the effective refractive index becomes zero at 4.35 GHz, and further propagates with a positive refractive index in the upper band ( (Right-handed mode)

FIG. 20 is a graph showing the reflection coefficient S11 and the transmission coefficient S21 of the transmission line of the three-dimensional metamaterial device according to the example of the present invention. FIG. 20 shows a simulation result of a three-dimensional metamaterial device (see FIG. 2) in which eight unit cells 10 are periodically arranged in the traveling direction of electromagnetic waves and infinite in the lateral direction. At both ends of the three-dimensional metamaterial device, dielectrics having a relative dielectric constant ε _r = 47 were provided so that impedance matching was achieved over a wide band, close to the value of the wave impedance of the designed three-dimensional metamaterial device. The model in FIG. 20 corresponds to propagation in the principal axis direction of the cubic lattice, that is, in the ΓX (100) direction in the dispersion curve in FIG. According to FIG. 20, it can be seen that a wide band pass characteristic is achieved from 4.15 GHz to 4.8 GHz, which is in good agreement with the band where the propagation mode exists in the previous dispersion curve.

  According to the above simulation, the metamaterial device according to the embodiment of the present invention can operate in a wider band than the conventional one while avoiding the conductor loss, and further realize a three-dimensional isotropic operation. I understand that I can do it.

  In addition, the present inventors have confirmed that both backward wave propagation and forward wave propagation occur in the three-dimensional metamaterial device according to the embodiment of the present invention, depending on the frequency of the input electromagnetic wave.

  The metamaterial apparatus according to the present invention includes a microwave circuit, its components and antennas (wide-angle beam scanning antenna, minute antenna, etc.), flat super lens, negative refractive flat lens, near-field imaging with sub-wavelength resolution, and cloaking technology. Can be applied to optical devices such as and the like and their components.

  As an application example of the present invention, there is a solution to radio interference by cloaking technology. In cities, radio waves are irregularly reflected by the construction of high-rise buildings, and there are many problems that signal propagation errors of video equipment and communication equipment increase. By surrounding the object (high-rise building) with a metamaterial device and optimizing the transmission characteristics of the electromagnetic wave in it, the object is made to bypass the electromagnetic wave, diffuse reflection is reduced, and the radio wave environment is improved. Cloaking).

  In addition, there is an example in which a blocking region that is a transition region between a left-handed system and a right-handed system is used to block or attenuate electromagnetic waves. This effect is effective in application to a mobile phone equipped with a plurality of wireless systems and digital circuits under severe mounting conditions. For example, in current mobile phones, 800 MHz band, 1500 MHz band, and 2 GHz band are used for telephone, 1.57 GHz is used for GPS, 470 to 710 MHz band is used for one-segment TV, and electronic money is used. The 13.56 MHz band is used to support such applications, and a plurality of antennas corresponding to the respective frequency bands are arranged in a narrow space of the casing of the mobile phone. In a small housing, communication performance deteriorates due to electromagnetic interference between antennas. In addition, unnecessary radiation of a clock signal from a circuit in the vicinity of these antennas is received as noise by the antenna, which causes a reduction in communication quality. Under such severe mounting conditions, it is effective to use a metamaterial device to control electromagnetic waves for each frequency and reduce mutual interference.

1, 1A, 1B ... dielectric resonator,
2 ... Host medium,
3, 3xa to 3xd, 3ya to 3yd, 3za to 3zd ... strip dielectric,
10, 10A to 10C ... unit cell,
20 ... One-dimensional metamaterial device,
21, 22 ... dielectric block,
30 ... Two-dimensional metamaterial device,
40, 40A ... 3D metamaterial device,
101, 102, 101-1, 102-1, ..., 101-N ... substrate layer,
111, 121 ... dielectric substrate,
112x, 112y, 122x, 122y ... linear dielectric pattern,
113, 123 ... through hole,
131 ... dielectric rod,
124 ... cavity,
P1, P2 ... ports.

Claims (9)

In a metamaterial device including a plurality of unit cells arranged periodically,
Each of the unit cells includes a dielectric resonator disposed in the center of the unit cell, a plurality of strip dielectrics disposed so as to surround the dielectric resonator, the dielectric resonator, and the strip dielectric. A host medium that supports the body,
In each of the unit cells, the plurality of strip dielectrics include at least one first strip dielectric disposed in a first direction and at least a second direction disposed in a second direction different from the first direction. One second strip dielectric and at least one third strip dielectric disposed in a third direction having a predetermined angle with respect to a plane stretched by the first and second directions;
In the metamaterial device configured by periodically arranging the plurality of unit cells, the first strip dielectrics are periodically and parallel to each other, and the second strip dielectrics are parallel to each other. And the third strip dielectrics are arranged in parallel and periodically with each other,
The metamaterial apparatus, wherein the dielectric resonator has a dielectric constant higher than a dielectric constant of the host medium, and the strip dielectric has a dielectric constant equal to or higher than a dielectric constant of the dielectric resonator.   The shape and size of the unit cell and the shape of the dielectric resonator so that the effective permittivity and effective permeability of the metamaterial device are both negative with respect to an electromagnetic wave having a predetermined frequency incident on the metamaterial device. , Dimensions, and relative dielectric constant, thickness of the strip dielectric, spacing between the first, second, and third strip dielectrics periodically, and relative dielectric constant of the host medium are set. The metamaterial device according to claim 1, wherein Each unit cell includes a waveguide formed by the plurality of strip dielectrics, each unit cell has a predetermined cutoff frequency, and each unit cell is incident on the metamaterial device. The effective dielectric constant of the metamaterial device is configured to be negative with respect to electromagnetic waves having a frequency lower than the off-frequency,
The dielectric resonator is excited by an electromagnetic wave having a predetermined frequency incident on the dielectric resonator in a resonance form having an electromagnetic field distribution similar to a magnetic dipole moment, and the metamaterial device effectively transmits the electromagnetic wave. The metamaterial device according to claim 2, wherein the metamaterial device is configured to have a negative magnetic permeability.   The metamaterial device according to claim 1, wherein each unit cell is a cube, and the first, second, and third directions are orthogonal to each other.   The metamaterial device according to claim 1, wherein the dielectric resonator has a spherical shape.   The metamaterial device according to claim 1, wherein the dielectric resonator has a cylindrical shape or a polygonal prism shape.   5. The metamaterial device according to claim 1, wherein the dielectric resonator has a cubic shape, a polyhedral shape, or a rhombohedral shape.   The combination of two unit cells adjacent to each other on one surface among the plurality of unit cells each share the strip dielectric on the one surface. The metamaterial apparatus as described in one of them. The host medium comprises a first substrate having a cavity and a second substrate sandwiching the first substrate, and the first strip dielectric is provided on the first substrate and / or the second substrate. And / or a second strip dielectric is formed,
The dielectric resonator is disposed in the cavity of the first substrate and formed in a unit form sandwiched between the second substrates, or formed in a state where two or more layers of the unit form are laminated. The metamaterial device according to claim 1, comprising the third strip dielectric.

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