CN109949842B - Racetrack memory based on Mags Gemcon - Google Patents
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Abstract
The invention provides a racetrack memory based on Magstar, which comprises a magnetic nanotube track, wherein the nanotube track is sequentially divided into an information writing part, an information storage part and an information reading part along the track direction; by using the presence or absence of MagnetitumRepresenting binary numbers '1' and '0', wherein Magstar is generated in the information writing part, then enters the information storage part along the nanotube track under the drive of current, and enters the information reading part to read data after passing through the information storage part; the racetrack memory has high information storage density and stability, and high read-write speed, and when the current density is 1013A/m2The axial propagation motion velocity of the siganus on the nanotube can reach 2000m/s, and the angular velocity of the siganus moving on the nanotube is related to the thickness of the nanotube, which is not possessed by the plane nanobelt structure.
Description
Technical Field
The invention belongs to the field of magnetic memories, and particularly relates to a racetrack memory based on Magnetitum.
Background
With the development of high and new technologies such as big data and artificial intelligence, people's demand for information storage increases day by day, and a storage device with higher storage density and higher reading speed is urgently needed. The racetrack memory is a novel nonvolatile memory, and compared with a traditional hard disk, the racetrack memory has higher storage density. Parin et al, 2008, have proposed a Magnetic Domain Wall-based Racetrack Memory (s.s.p.parin, et.al Magnetic Domain-Wall Racetrack Memory). The racetrack memory encodes binary information by spin-up and spin-down magnetic domains, stores data on a nanobelt similar to a magnetic tape, and writes and reads data by applying spin-polarized current to drive the magnetic domains to corresponding write-read positions.
Magnetite is a topologically protected magnetic structure that has significant advantages in racetrack storage applications due to its small size and high stability. In a magnetic skybird-based racetrack memory, binary code compilation is performed with the presence or absence of skybirds, which represent "1" and "0" on the contrary. Magnetic skyburn based racetrack memories have many advantages over magnetic domain based racetrack memories. First, the initiation current required to drive the conventional domain wall is about 2.5 × 10 in power consumption11A/m2The starting current for driving the Stargargin is only 106A/m2Thus, the power consumption of the magnetic skyscraper-based racetrack memory is lower. In addition, the size of the magnesegrain is smaller, typically between a few nanometers to tens of nanometers, compared to the domain wall, and racetrack memories using magnesegrain as the information carrier have higher storage densities.
When the magnetic skulls are driven by spin-polarized current, the direction of movement of the skulls is deflected towards the edges of the nanoribbon due to the effect of the magnus force, the so-called skulls hall effect. When the skullet moves to the boundary of the nano-orbit, the boundary will generate the stress force to the skullet. When the current density is larger than a certain value, the acting force of the boundary to the sggmen is far smaller than the Magnus force, and the sggmen is annihilated at the boundary of the nano-orbit. In the magnetic skyscraper-based racetrack memory, the data reading speed depends on the moving speed of the skyscraper, and the validity of information depends on whether the skyscraper can stably move on a nano track or not. Therefore, overcoming the effect of the skullet effect and keeping skullet stable in high speed motion on the nano-track is based on the problem that the magnetic skullet racetrack memory needs to solve.
Disclosure of Invention
In view of the above-mentioned drawbacks of the prior art, the object of the present invention is to propose a magnetic skutter-based racetrack memory, replacing the traditional planar nano-tracks with nanotube tracks, aiming at avoiding the movement of skutters to the disappearance of the borders by eliminating the borders themselves. Because the tubular structure is a closed geometric curved surface, under the drive of current, the sigramins move on the nanotube along a spiral track. The nanotube structure is used as the track of the racetrack memory, and when the current is increased, the siganus can keep stable and high-speed motion on the track, so that the stability of the racetrack memory based on the magnesiosis is greatly improved.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a racetrack memory based on Magstar comprises a magnetic nanotube track, wherein the nanotube track is sequentially divided into an information writing part, an information storage part and an information reading part along the track direction;
binary numbers '1' and '0' are represented by the existence of magnetic skybromons which represent '1' and '0' in the absence of magnetic skybromons, and the magnetic skybromons represent '1' and '0' in the opposite direction, are generated in the information writing part, then move along the nanotube track under the drive of current to enter the information storage part, and enter the information reading part to read data after passing through the information storage part.
Preferably, in a single writing period, a first current is injected into the magnetic tunnel junction of the information writing part, the direction of the first current is perpendicular to the surface of the magnetic nanotube and inward, the first current is firstly polarized into a spin polarization current through the fixed layer, the spin direction of the spin polarization current is the same as that of the magnetic moment of the fixed layer, when the first current flows to the nanotube track, a Magssessmen is generated at the position of the information writing part of the nanotube, and further a binary number "1" is represented, and conversely a binary number "0" is represented, and the first current determines whether to apply current in each writing period according to the logic requirement of writing.
Preferably, the information writing part is formed by sleeving a semi-annular Magnetic Tunnel Junction (MTJ) on the outer surface of one end of the nanotube.
Preferably, after the single writing period is finished, a single transmission period is entered, in the single transmission period, a second current along the nanotube track direction is injected into the nanotube track, the meglumine moves along the nanotube track under the driving of the second current and enters the information storage part, so that the single bit of information is stored, the second current is a periodical spin-polarized pulse current, the period of the second current is the time for the meglumine to move from the position of one storage unit to the position of the next storage unit, and the application time is after each writing period.
Preferably, the magnetoseguin moves along a spiral track on the nanotube under the driving of the second current, and the upward speed of the angular direction of the magnetoseguin increases along with the increase of the thickness of the nanotube.
Preferably, the information storage portion is divided into a plurality of memory cells along the nanotube track, each memory cell storing one bit of information corresponding to the presence or absence of a state of magnetorsin at each memory cell position.
Preferably, in a single reading period, a third current is injected inwards in a direction perpendicular to the nanotube surface in the magnetic tunnel junction of the information reading part, and whether the siganus are passing through is further judged by detecting the change of the tunnel magnetoresistance of the information reading part, and when the siganus pass through the nanotube track of the information reading part, the high resistance state is obtained, and otherwise, the low resistance state is obtained.
Preferably, the information reading part is formed by sleeving an annular magnetic tunnel junction at one end of the nanotube far away from the information writing part, and detecting whether the siganus passes through or not by detecting the change of the magnetic resistance.
Preferably, the material used for the magnetic nanotube is a magnetic bulk material with bulk DM interaction, and the direction of anisotropy is perpendicular to the nanotube surface and outward.
Preferably, the material used for the magnetic nanotube is B20 bulk material with inverted symmetry and defect of atomic structure, and is selected from MnSi, FeGe, FeCoSi, Cu2OSeO3MnGe, the sgg formed is of bloch type, the magnetic nanotubes having an anisotropy direction along the radial direction.
The invention has the beneficial effects that:
(1) the track of the traditional magnetic skysave-based racetrack memory is a planar nanobelt structure, when current is used for driving skysave, due to the hall effect of skysave, skysave can deviate from the nanobelt track to move, and when the boundary of the nanobelt is touched, skysave can be annihilated at the boundary, so that information loss or misreading is caused. The invention replaces the plane nano-tube structure with the nano-tube structure, and the structure of the nano-tube is a closed curved surface, so that the siganus oramin can still be stably transmitted on the nano-tube even if a large current is applied.
(2) Compared with the traditional racetrack memory based on a magnetic domain wall type, the racetrack memory based on the Magnesquerite on the nanotube has higher information storage density and stability.
(3) The racetrack memory has high read-write speed, and the current density is 1013A/m2The axial propagation motion speed of the skynergons on the nanotube can reach 2000 m/s.
(4) The angular velocity of the siganus moving on the nanotube is related to the thickness of the nanotube, for example, when the outer radius of the nanotube is fixed and the inner radius of the nanotube is reduced, the angular velocity of the siganus is increased, which is not provided in the planar nanobelt structure.
Drawings
FIG. 1 is an example of a magnetic skyburn-based nanotube racetrack memory, with skyburn representing a binary "1" and vice versa representing a "0".
2 is an information writing section, 3 is an information storage section, 4 is an information reading section, 5 is a semicircular magnetic tunnel junction, 6 is an annular magnetic tunnel junction, and 7 is a magnetic nanotube track.
Detailed Description
The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.
A racetrack memory based on Magstar comprises a magnetic nanotube track, wherein the nanotube track is sequentially divided into an information writing part, an information storage part and an information reading part along the track direction;
binary numbers '1' and '0' are represented by the existence of magnetic skybromons which represent '1' and '0' in the absence of magnetic skybromons, and the magnetic skybromons represent '1' and '0' in the opposite direction, are generated in the information writing part, then move along the nanotube track under the drive of current to enter the information storage part, and enter the information reading part to read data after passing through the information storage part.
The information writing part is formed by sleeving a semi-annular Magnetic Tunnel Junction (MTJ) on the outer surface of one end of the nanotube.
In a single writing period, injecting a first current into the magnetic tunnel junction of the information writing part, wherein the direction of the first current is perpendicular to the surface of the magnetic nanotube and faces inwards, the first current is firstly polarized into a spin polarization current through the fixed layer, the spin direction of the spin polarization current is the same as that of the magnetic moment of the fixed layer, when the first current flows to the nanotube track, a MagsGegmon is generated at the position of the information writing part of the nanotube, and then a binary number '1' is represented, otherwise, a binary number '0' is represented, and the first current determines whether to apply current in each writing period according to the logic requirement of writing.
And entering a single transmission period after the single writing period is finished, wherein in the single transmission period, a second current along the direction of the nanotube track is injected into the nanotube track, and the meglumine moves along the nanotube track under the driving of the second current to enter the information storage part so as to store single bit information, wherein the second current is a periodical spin-polarized pulse current, the period of the second current is the time for the meglumine to move from the position of one storage unit to the position of the next storage unit, and the application time of the second current is after each writing period.
Under the drive of the second current, the magnetoseguin moves on the nanotube along a spiral track, and the angular upward speed of the magnetoseguin increases along with the increase of the thickness of the nanotube (for example, the outer radius of the nanotube is fixed, and the inner radius of the nanotube is reduced).
The information storage section is divided into a plurality of memory cells along the nanotube tracks, each memory cell storing one bit of information corresponding to the presence or absence of a state of a magnetosensitive.
The information reading part is characterized in that one end of the nanotube far away from the information writing part is sleeved with an annular magnetic tunnel junction, in a single reading period, a third current is injected inwards in a direction perpendicular to the surface of the nanotube in the magnetic tunnel junction of the information reading part, whether the siganus passing through is judged by detecting the change of Tunnel Magnetic Resistance (TMR) of the information reading part, and when the siganus passing through the nanotube track of the information reading part, the tunnel magnetic resistance is large in edge and is in a high-resistance state, otherwise, the tunnel magnetic resistance is in a low-resistance state.
The material used by the magnetic nanotube is a magnetic bulk material with bulk DM interaction (Dzyaloshinkii-Moriya interaction), and the direction of anisotropy is perpendicular to the surface of the nanotube and faces outwards.
The material used by the magnetic nanotube is B20 bulk material with inverted and symmetrical atomic structure and is selected from MnSi, FeGe, FeCoSi, Cu2OSeO3MnGe, a material of this type with bulk DM interaction (Dzyaloshinkii-Moriya interaction), the sgermines formed being those of the Bloch skyrmion type. The magnetic nanotubes have an anisotropy direction along a radial direction.
In this embodiment, the outer radius of the magnetic nanotube is 50nm, the inner radius is 30nm, the length of the nanotube is 400nm, the distance between each memory cell is 50nm, the magnetic material used is FeGe, and the direction of anisotropy is perpendicular to the surface of the nanotube and faces outwards.
As shown in FIG. 1, a first current j is applied to the write headwWith the direction of current flow directed perpendicular to the nanotube surface inward for application toThe nanotubes have a magnetic skyburn formed thereon, defining the binary number "1" represented at this time, and the binary number "0" otherwise. After formation of the skullet, at a second current jdDriven by the driving unit, the sgrming moves along the nanotube track from the write head to the information storage portion. Finally, a third current j is applied to the read headrThe direction of current flow is perpendicular to the nanotube surface inward, and when a sigecun passes the read head, the tunnel magnetoresistance of the read head becomes large, reading a binary number "1", and conversely "0".
The working process of the invention is detailed below by taking the stored data as "01101" as an example.
First write cycle T1In the write head, a first current j is injected perpendicular to the nanotube surfacewAt 0, no magneto-optic germine is generated in the information writing portion of the nanotube, thereby representing a binary number "0".
After the first write cycle is finished, the first current j is turned offwEnter the first transmission period T2. In the time of the first transmission period, a second current j is introduced to the nanotubedWith the direction along the axis of the nanotube. After the first transmission period is finished, the second current jdAnd closing. The information stored in the first memory cell in the information storage portion of the nanotube at this time is "0". The single write cycle and the transfer cycle constitute one complete single bit storage period T.
Entering a second writing period, wherein a first current j is injected to the writing head perpendicular to the nanotube surfacewThe skulls are generated in the written portion of the nanotube, representing a binary "1".
After the second write cycle is finished, the first current j is turned offwAnd entering a second transmission period. In the time of the second transmission period, a second current j is introduced to the nanotubedThe spout is driven to move to the first storage unit of the information storage portion. At this time, the first memory cell in the information storage portion of the nanotube is "1" and the second memory cell is "0". The second storage cycle ends.
A third storage cycle is entered. A first current j injected perpendicular to the nanotube surface at the write head during a write cyclewThe segregant is generated in the written portion of the nanotube. In the transmission period, a second current j is introduced to the nanotubedThe movement of the spout is driven to the first storage unit of the information storage portion, and the spout originally in the first storage unit is moved to the second storage unit. At this time, the first memory cell in the information storage portion of the nanotube is "1", the second memory cell is "1", and the third memory cell is "0". The third storage period ends.
By analogy, after 5 storage periods are finished, the states of the skynerger are sequentially 'none', 'existence', 'absence', 'existence', and 'existence', namely, the stored data is '01101', starting from the fifth storage unit and finishing from the first storage unit.
When data needs to be read, the first transmission cycle is entered. In the first transmission period, a second current j is introduceddThe information in the nanotube information storage unit is shifted to the right by one bit and the information originally in the fifth storage unit is shifted to the read head. After the first transmission period is finished, the second current jdTurning off, entering the first reading period, and injecting a third current j into the reading head of the information reading part during the first reading periodrWith the direction of current flow perpendicular to the nanotube surface inward. The tunnel magnetoresistance is read at this time as a low resistance state, and a binary number "0" is read.
And entering a second transmission period after the first reading period is finished. In the second transmission period, a second current j is introduceddThe state of the reference state of the fifth memory cell is "present", "absent", and "present" in the information storage portion. After the second transmission period, the second current jdAnd closing and entering a second reading period. In the second reading period, the reading head in the information reading part injects a third current jrAt this time, since a magnetic skyrmion is present at the position of the read head, the magnetic tunnel resistance is in a high resistance state, and the binary number "1" is read.
By analogy, after 5 reading periods, all the stored information of the nanotube information storage part can be read.
In some embodiments, when the current density is 1013A/m2The moving speed of the Magstar is about 2000m/s, and the pulse current jdPeriod T of2＝50nm/(2000m/s)＝0.025ns。
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.
Claims (1)
1. A race track memory based on a magnesiate, characterized by: the magnetic nanotube track is sequentially divided into an information writing part, an information storage part and an information reading part along the track direction;
the binary numbers '1' and '0' are represented by the existence of magnetic skybromons, the existence of the magnetic skymromons represents '1', and the existence of the magnetic skymromons represents '0', the magnetic skymons are generated in the information writing part, then move along a nanotube track under the drive of current to enter the information storage part, and enter the information reading part to read data after passing through the information storage part;
injecting a first current into the magnetic tunnel junction of the information writing part in a single writing period, wherein the direction of the first current is perpendicular to the surface of the magnetic nanotube and faces inwards, the first current is firstly polarized into a spin polarization current through the fixed layer, the spin direction of the spin polarization current is the same as that of the magnetic moment of the fixed layer, when the first current flows to the nanotube track, a Magstar is generated at the position of the information writing part of the nanotube, and then a binary number of 1 is represented, otherwise, a binary number of 0 is represented, and the first current determines whether to apply the current in each writing period according to the logic requirement of writing;
the information writing part is formed by sleeving a semi-annular Magnetic Tunnel Junction (MTJ) on the outer surface of one end of the nanotube;
entering a single transmission period after the single writing period is finished, and in the single transmission period, injecting a second current along the direction of the nanotube track into the nanotube track, wherein the magnesiogmine moves along the nanotube track under the driving of the second current and enters the information storage part so as to store single bit information, the second current is a periodical spin-polarized pulse current, the period of the second current is the time for the magnesiogmine to move from the position of one storage unit to the position of the next storage unit, and the application time is after each writing period;
under the drive of a second current, the Magstar moves on the nanotube along a spiral track, and the angular upward speed of the Magstar increases along with the increase of the thickness of the nanotube;
the information storage section is divided into a plurality of memory cells along the nanotube tracks, each memory cell storing one bit of information corresponding to the presence or absence of a magneto-optical grating at each memory cell location;
in a single reading period, injecting a third current inwards in a direction perpendicular to the surface of the nanotube at the magnetic tunnel junction of the information reading part, and detecting the change of the tunnel magnetic resistance of the information reading part to further judge whether a Magstar passes through, wherein when the Magstar passes through the nanotube track of the information reading part, the Magstar is in a high-resistance state, and otherwise, the Magstar is in a low-resistance state;
the information reading part is characterized in that one end of the nanotube far away from the information writing part is sleeved with an annular magnetic tunnel junction, and whether the Magstar passes through or not is detected by detecting the change of the magnetic resistance;
the material used by the magnetic nanotube is a magnetic block material with block DM interaction, and the direction of anisotropy is perpendicular to the surface of the nanotube and faces outwards;
the material used by the magnetic nanotube is B20 bulk material with inverted and symmetrical atomic structure and is selected from MnSi, FeGe, FeCoSi, Cu2OSeO3MnGe, the magnesiogmine formed is a bloch type magnesiogmine, the magnetic nanotubes having an anisotropy direction along the radial direction.
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| CN110535460B (en) * | 2019-09-23 | 2021-08-24 | 四川师范大学 | Novel logic gate circuit based on antiferromagnetic siganmin |
| CN113497180A (en) * | 2020-04-03 | 2021-10-12 | 中国科学院苏州纳米技术与纳米仿生研究所 | Spin memristor synapse device based on sigermin |
| CN111768806B (en) * | 2020-06-12 | 2022-05-31 | 华南师范大学 | Magnetic skynet based memory device and method for storing information by using same |
| CN111951846B (en) * | 2020-08-14 | 2022-10-28 | 长江存储科技有限责任公司 | Track memory, reading and writing method thereof and track memory device |
| WO2024011407A1 (en) * | 2022-07-12 | 2024-01-18 | 中国科学院微电子研究所 | Memory cell and preparation method therefor, memory, and information storage method |
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Inventor after: Yan Peng Inventor after: Cao Yunpan Inventor after: Wang Xiaofan Inventor after: Wang Xiansi Inventor after: Wang Chen Inventor after: Yang Huanhuan Inventor before: Yan Peng Inventor before: Cao Yunshan Inventor before: Wang Xiaofan Inventor before: Wang Xiansi Inventor before: Wang Chen Inventor before: Yang Huanhuan |