Spin wave waveguide structure

Abstract

The present invention is a spin wave waveguide structure having: an insulating magnetic body film; and a periodic conductor film that is positioned on at least one surface among both surfaces of the insulating magnetic body film, and comprises a conductor film having a periodic structure. The periodic structure of the periodic conductor film is such that the conductor film comprises an aggregate of a plurality of fragment films, the fragment films are electrically insulated from each other, and this insulation is due to the fragment films being separated from each other by a plurality of holes and a groove linking the plurality of holes, or due to a non-magnetic and non-conductive material being present in at least one section of the holes and groove. On the insulating magnetic body film, there is a section that has the periodic conductor film and a section that does not have the conductor film, and the insulating magnetic body film in the section not having the conductor film functions as a spin wave waveguide. Thus, a spin wave waveguide structure that is capable of guiding spin waves without changing the shape of a magnetic material is provided.

Description

Spin wave guide structure

[0001] The present invention relates to a spin-wave waveguide structure.

[0002] In recent years, the rapid increase in the amount of information generated by the Internet and artificial intelligence has created a demand for continuous growth in electronic devices. Until now, performance improvements have been achieved through the miniaturization and integration of electronic devices. However, as miniaturization approaches its physical limits, the problem of heat generation has become more pronounced, ultimately hindering device performance improvements. This heat generation is caused by Joule heat generated when electrons move through conductors. It is believed that this problem can be solved by developing devices that process information without electron movement. Therefore, attention has been focused on devices using spin waves, which can propagate through electrically non-conductive insulators without the need for electron movement. However, the development of spin wave devices has only rapidly gained attention over the past decade. Basic components, such as spin wave propagation elements and rudimentary logic elements, have been steadily developed, and as of 2023, they are still in their infancy.

[0003] Against this background, methods and structures for realizing waveguides, the most basic element of spin wave devices (spin wave circuits), have been developed. Spin wave waveguides are equivalent to electric wires (wiring) in electronic circuits and can be said to be essential. Spin waves are phase waves created by magnetization (spin) in magnetic materials. They are also called magnetostatic waves. In the explanations in this specification, spin waves are a concept that includes "magnetostatic waves."

[0004] Spin waves propagate only within magnetic materials and not in air. Therefore, spin wave wiring is possible by processing magnetic materials into any shape. Waveguides of any shape are usually fabricated by etching or cutting out magnetic materials. Non-Patent Document 1 presents an example of fabricating a spin wave waveguide by cutting out a magnetic material into a Ψ shape, as shown in Figure 1. This makes it possible to wire spin waves at any location. However, changing the shape of a magnetic material changes the magnetization state, which changes the propagation strength of the spin waves, resulting in a problem of degraded power efficiency of spin wave devices. This change in magnetization state caused by a change in the shape of a magnetic material is a principle common to all magnetic materials, and there is no way to avoid it as long as the shape is changed.

[0005] By periodically drilling holes in a magnetic material, a periodic magnetization structure can be created. Of the spin waves propagating through a magnetic material with periodically formed holes, only spin waves of a specific frequency cannot propagate due to phase interference. This range of frequencies that cannot propagate is called a band gap. By creating a region within the periodic structure where there is no periodic structure, spin waves can propagate along that region. Non-Patent Document 2 is a paper that experimentally demonstrates this. However, because the shape of the magnetic material in Non-Patent Document 2 is changed, the propagation strength of the spin waves changes, as in Non-Patent Document 1, and the power efficiency of spin wave devices remains a significant degradation issue.

[0006] Naoki Kanazawa, Taichi Goto, Koji Sekiguchi, Alexander B. Granovsky, Caroline A. Ross, Hiroyuki Takagi, Yuichi Nakamura, Hironaga Uchida and Mitsuteru Inoue, "The role of Snell's law for a magnonic majority gate", Scientific Reports, 7, 7898 (2017 / 08 / 11).Y. Zhu, KH Chi and CS Tsai, "Magnonic crystals-based tunable microwave phase shifters", Applied Physics Letters, 105, 022411 (2014).

[0007] As described above, a spin wave waveguide is required to realize spin wave wiring. Non-Patent Documents 1 and 2 disclose structures for fabricating a spin wave waveguide. However, both of the structures in Non-Patent Documents 1 and 2 require the shape of the magnetic material to be changed by processing, and it is known that the shape dependency of the magnetic material deteriorates the propagation efficiency (power consumption) of the spin wave. For this reason, a structure that controls the guiding direction of the spin wave without changing the shape of the magnetic material has been sought. This is a challenge for modern spin wave waveguides. An effective structure to solve this problem has not yet been proposed.

[0008] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide a spin wave waveguide structure capable of guiding spin waves without changing the shape of the magnetic material.

[0009] In order to achieve the above object, the present invention provides a spin-wave waveguide structure for guiding spin waves, comprising an insulating magnetic film and a periodic conductor film made of a conductor film having a periodic structure arranged on at least one of both surfaces of the insulating magnetic film, wherein the periodic structure of the periodic conductor film is such that the conductor film is made of an aggregate of a plurality of small film fragments, and the small film fragments are electrically insulated from adjacent small film fragments, and the electrical insulation of the small film fragments is achieved by separating the small film fragments by a plurality of holes and grooves connecting the plurality of holes, or by the presence of a nonmagnetic and nonconductive material in at least some of the holes and grooves, and the spin-wave waveguide structure has a portion on the insulating magnetic film that has the periodic conductor film and a portion on the insulating magnetic film that does not have the conductor film, and the insulating magnetic film in the portion that does not have the conductor film functions as a spin-wave waveguide.

[0010] Such a spin-wave waveguide structure enables spin-wave guiding without changing the shape of the magnetic material. That is, the portion of the insulating magnetic film that does not have a conductive film can function as a spin-wave waveguide, and spin-wave guiding is possible by changing the location of the conductive film without changing the shape of the insulating magnetic film.

[0011] Here, it is preferable that the insulating magnetic film is made of magnetic garnet, and more preferably, the insulating magnetic film is made of yttrium iron garnet.

[0012] By using such a type of insulating magnetic film, it is possible to achieve good spin wave guiding.

[0013] The conductive film may contain at least one of copper, aluminum, gold, silver, platinum, iron, a transparent conductor, a superconductor, graphene, carbon nanotubes, an organic conductive material, and a conductive magnetic material.

[0014] In the spin-wave waveguide structure of the present invention, the above-mentioned types of conductors can be used in addition to copper as the conductor component.

[0015] It is also preferable that the insulating magnetic film has a thickness of 1 mm or less.

[0016] It is also preferable that the thickness of the conductive film is 100 μm or less.

[0017] The dimensions of the components of the spin-wave waveguide structure of the present invention are preferably as described above, and can be made compact.

[0018] Preferably, the spin-wave waveguide structure further comprises a support substrate, on which the insulating magnetic film and the periodic conductive film are disposed.

[0019] In this way, the spin-wave waveguide structure further includes a support substrate, and thus can have excellent mechanical strength.

[0020] In this case, the support substrate can be at least one of a silicon substrate, a glass substrate, a garnet substrate, a dielectric substrate, a conductive substrate, an insulating substrate, a magnetic substrate, a non-magnetic substrate, a wood substrate, and a stone substrate.

[0021] In the spin-wave waveguide structure of the present invention, the above-mentioned types of substrates can be used as the support substrate in addition to a silicon substrate.

[0022] The thickness of the support substrate is preferably 100 μm or more and 500 μm or less.

[0023] In consideration of strength and miniaturization, it is preferable that the thickness of the support substrate be within this range.

[0024] Furthermore, an input section and an output section for spin waves may be formed in the insulating magnetic film in a portion not having the conductive film.

[0025] A spin wave waveguide structure having such an input section and an output section can easily input and output spin waves.

[0026] The spin-wave waveguide structure of the present invention enables spin-wave guiding without changing the shape of the magnetic material. That is, the portion of the insulating magnetic film that does not have a conductive film can function as a spin-wave waveguide, and spin-wave guiding is possible by changing the location of the conductive film without changing the shape of the insulating magnetic film.

[0027] 2 is a schematic top view showing an example of a spin-wave waveguide structure of the present invention; FIG. 3 is a schematic top view showing an example of a spin-wave waveguide structure of the present invention, and is an enlarged view of the portion indicated by the dashed line A in FIG. 1; FIG. 4 is a cross-sectional view showing an example of a spin-wave waveguide structure of the present invention, and is a cross-sectional view of the portion indicated by the dashed line B in FIG. 2; FIG. 5 is a cross-sectional view showing an example of an output section that can be formed in the spin-wave waveguide structure of the present invention; FIG. 6 is a diagram showing the propagation of spin waves in an example; FIG. 7 is a graph showing the intensity distribution of spin waves measured at output terminals (output section and comparative output section) of the example; and FIG. 8 is a diagram showing the propagation of spin waves in a comparative example.

[0028] Hereinafter, the present invention will be described in detail with reference to the preferred embodiments, but the present invention is not limited to these.

[0029] As described above, there has been a demand for a structure that controls the direction of spin wave guidance without changing the shape of the magnetic material. In response to this problem, the inventors discovered that a specific structure enables spin wave guidance without changing the shape of the magnetic material, and have completed the present invention.

[0030] The present invention provides a spin-wave waveguide structure for guiding spin waves, comprising an insulating magnetic film and a periodic conductor film made of a conductor film having a periodic structure arranged on at least one of both surfaces of the insulating magnetic film, wherein the periodic structure of the periodic conductor film is such that the conductor film is made of an aggregate of a plurality of small film fragments, and the small film fragments are electrically insulated from adjacent small film fragments, and the electrical insulation of the small film fragments is achieved by separating the small film fragments by a plurality of holes and grooves connecting the plurality of holes, or by the presence of a nonmagnetic and nonconductive material in at least some of the holes and grooves, and the spin-wave waveguide structure has a portion on the insulating magnetic film having the periodic conductor film and a portion on the insulating magnetic film not having the conductor film, and the insulating magnetic film in the portion not having the conductor film functions as a spin-wave waveguide.

[0031] The present invention will be further described with reference to the drawings. Fig. 1 is a schematic top view showing an example of a spin-wave waveguide structure of the present invention. Fig. 2 is an enlarged view of a portion surrounded by dashed line A in Fig. 1. Fig. 3 is a cross-sectional view of a portion surrounded by dashed line B in Fig. 2. Fig. 4 is a cross-sectional view showing an example of an output section.

[0032] The spin-wave waveguide structure 100 shown in FIGS. 1 to 4 includes an insulating magnetic film 12 and a periodic conductive film 14. The periodic conductive film 14 is disposed on at least one of both surfaces of the insulating magnetic film 12. Here, as shown in the cross-sectional view of FIG. 3, an example is shown in which the periodic conductive film 14 is formed on both surfaces of the insulating magnetic film 12. Furthermore, as shown in FIGS. 1 and 2, the periodic conductive film 14 has a periodic structure. Furthermore, the periodic structure of the periodic conductive film is such that the conductive film is an aggregate of small film fragments 14a separated by a plurality of holes 15 and grooves 16 connecting the plurality of holes 15, and these holes 15 and grooves 16 electrically insulate the small film fragments 14a from adjacent small film fragments 14a.

[0033] 1, the spin-wave waveguide structure 100 has a portion having a periodic conductor film 14 on an insulating magnetic film 12 and a portion having no conductor film on the insulating magnetic film. The insulating magnetic film 12 in the portion having no conductor film functions as a spin-wave waveguide. In FIG. 1, the spin-wave guiding direction 21 is indicated by a dashed line. The portion of the insulating magnetic film 12 that functions as a spin-wave waveguide must have no conductor film, regardless of the periodicity.

[0034] With this structure, a spin wave guide structure capable of guiding spin waves can be obtained without changing the shape of the magnetic material (insulating magnetic film 12).

[0035] 1 is an example in which a spin wave input section 22 and an output section 24 are formed in the insulating magnetic film 12 in a portion not including a conductive film. A spin wave waveguide structure having such an input section 22 and an output section 24 can easily input and output spin waves.

[0036] In the example of FIG. 1 , a portion without a conductive film, i.e., a spin-wave waveguide, is formed between the input section 22 and the output section 24, and the spin-wave waveguide is bent between the input section 22 and the output section 24. While the bending angles α and β are 120° in FIG. 1 , other angles are also possible. For example, it is possible to fabricate a waveguide bent at a right angle by setting the bending angles α and β to 90°. The bending angles α and β can also be less than 90°, for example, at 10°, and the output terminal can be positioned so that it returns to the input terminal immediately next to it. Note that FIG. 1 also shows an example in which the comparison output section 26 also has an output section in the portion having the periodic conductive film 14 (the portion that is not a spin-wave waveguide). However, as described below, spin waves hardly propagate through this comparison output section 26.

[0037] The spin-wave waveguide structure 100 shown in FIG. 1 has an insulating magnetic film 12 in all regions, including the input section 22 and the output section 24. This insulating magnetic film 12 is made of a magnetic material, preferably made of magnetic garnet, and particularly preferably made of yttrium iron garnet (commonly known as YIG). Magnetic materials such as YIG inherently allow spin waves to propagate, and spin waves propagate within the x-y plane in FIG. 1. If the insulating magnetic film 12 in FIG. 1 did not have any conductive film 14, spin waves would propagate without restriction, but the structure shown in FIG. 1 makes it possible to restrict the propagation of spin waves to a path that functions as a spin-wave guide.

[0038] YIG is a magnetic material and an insulator, a magnetic insulator. ３ Fe ５ O １２ The insulating magnetic film 12 of the present invention is based on the above, and may be made of a material in which the Y portion or the Fe portion is substituted with other elements. The important thing about the material for the insulating magnetic film 12 is that it is a magnetic material and an insulator, and magnetic garnet is particularly preferable, and among them, YIG is particularly known for its small damping constant, and a small damping constant results in little dissipation of spin waves, so that good spin wave propagation can be obtained. The damping constant of the material forming the insulating magnetic film is 1×10 －３ Below, 1 x 10 －７ The above is preferable.

[0039] In the spin-wave waveguide structure 100 of the present invention, the thickness of the insulating magnetic film 12 can be set to 1 mm or less. This thickness is sufficient and allows the spin-wave waveguide structure to be miniaturized. There is no particular lower limit to the thickness of the insulating magnetic film 12, but for example, it can be set to 0.01 μm or more for reasons such as ease of processing.

[0040] In the spin-wave waveguide structure 100 of the present invention, the periodic conductive film 14 may be made of any conductive material, including at least one of copper, aluminum, gold, silver, platinum, iron, a transparent conductor, a superconductor, graphene, carbon nanotubes, an organic conductive material, and a conductive magnetic material, of which copper is particularly preferred.

[0041] As shown in Figures 1 and 2, the small pieces of film 14a preferably have a triangular shape with rounded edges (especially made of copper). The periodic conductive film 14 is a periodic structure in which these small pieces of film 14a are periodically arranged. Adjacent small pieces of film 14a do not contact each other and are electrically insulated from each other. If no special material is formed between adjacent small pieces of film 14a (holes 15 and grooves 16), air is used, electrically insulating adjacent small pieces of film 14a. Since it is sufficient to insulate the small pieces of film 14a from each other, the material between adjacent small pieces of film 14a is not particularly limited as long as it is nonmagnetic and nonconductive. In other words, electrical insulation between the small pieces of film 14a can also be achieved by the presence of a nonmagnetic and nonconductive material in at least a portion of the holes 15 and grooves 16. Examples of materials between adjacent small pieces of film 14a include glass, silicon, silicone, and plastic. The nonmagnetic and nonconductive material may fill the entire holes 15 and grooves 16, or may be present in only a portion of the holes 15 and grooves 16. Figures 1 to 3 show a case where nothing is formed between adjacent small film pieces 14a.

[0042] The periodic conductive film 14, which is composed of numerous small film fragments 14a, can have the following dimensions. As shown in Figures 2 and 3, the size of the holes 15 is d, the width of the linear grooves 16 connecting the holes 15 is g, and the center-to-center distance between two holes 15 is a. Because adjacent holes 15 are connected by linear grooves 16, the small film fragments 14a are not in contact with each other and are isolated. The appropriate values ​​for the structure size (d, g, a, the thickness of the conductive film, and the thickness of the insulating magnetic film 12) vary depending on the frequency and wavelength of the spin waves and the physical properties of the magnetic material constituting the insulating magnetic film 12. If the insulating magnetic film 12 is YIG and has a thickness of 10 μm, and the periodic conductive film 14 is made of copper, the constants d, g, and a can be more specifically set to 250 μm, 1 μm, and 450 μm, respectively.

[0043] The periodic conductive film 14 preferably has a thickness of 100 μm or less. This thickness is sufficient for the periodic conductive film 14 and allows for miniaturization. There is no particular lower limit to the thickness of the periodic conductive film 14, but it can be set to 0.001 μm or more, for example, for reasons of ease of processing.

[0044] As a more specific example, the periodic structure of the spin-wave waveguide structure 100 can be one in which both the upper and lower surfaces are covered with 2 μm thick copper (conductor) having periodic holes 15 and grooves 16, as shown in FIGS. 1 to 3 .

[0045] Spin wave guiding is possible even if the periodic conductive film 14 is formed on only one side of the insulating magnetic film 12. However, it is preferable that the periodic conductive film 14 exists on both sides at the same time, as this makes it easier to control the guiding of spin waves. When the periodic conductive film 14 exists on both sides of the insulating magnetic film 12, it is preferable that the periodic conductive films 14 exist symmetrically on both sides with the insulating magnetic film 12 as the boundary.

[0046] The entire device of the spin-wave waveguide structure 100 of the present invention may be formed on a support substrate. That is, the spin-wave waveguide structure 100 may further include a support substrate (not shown), on which the insulating magnetic film 12 and the periodic conductive film 14 are disposed. By including a support substrate, the spin-wave waveguide structure 100 can have excellent mechanical strength. The support substrate is preferably at least one of a silicon substrate, a glass substrate, a garnet substrate, a dielectric substrate, a conductive substrate, an insulating substrate, a magnetic substrate, a non-magnetic substrate, a wood substrate, and a stone substrate. The thickness of the support substrate may be 100 μm or more and 500 μm or less. More specific preferred examples of the support substrate include a silicon substrate, a glass substrate, and a garnet substrate, each having a thickness of several hundred μm.

[0047] As shown in FIGS. 1 and 4 , the input section 22 (input terminal) and the output section 24 (output terminal) may have a conductor film 23 and a conductor film 25 formed on top of the magnetic film 12, respectively. The input section 23 and the output section 25 may be, for example, gold films with a thickness of 30 nm. These gold films suppress excess reflected spin waves that may occur at the ends of the input and output terminals. These films are provided to facilitate confirmation of the performance of the spin-wave guided periodic structure and are well-known structures that appear in Non-Patent Document 1. The input section 23 and the output section 25 may contain at least one of gold, copper, aluminum, silver, platinum, iron, a transparent conductor, a superconductor, graphene, carbon nanotubes, an organic conductive material, and a conductive magnetic material.

[0048] The dimensions of the input section 22 and the output section 24 are arbitrary, but D1 in Figures 1 and 4 can be set to 2 mm, D2 to 2 mm, and D3 to 0.3 mm. The dimensions of the comparison output section 26 and its conductive film 27 are also similar.

[0049] EXAMPLES The present invention will be explained in more detail below by showing examples and comparative examples of the present invention, but the present invention is not limited to these examples.

[0050] [Example] A spin-wave waveguide structure according to the present invention, as shown in Figs. 1 to 4, was fabricated. The insulating magnetic film 12 was made of YIG, and the periodic conductive films 14 arranged on both sides of the insulating magnetic film 12 were made of copper. The periodic conductive films 14 on both sides of the insulating magnetic film 12 were symmetrical with respect to the insulating magnetic film 12. The conductive film 23 of the input section 22, the conductive film 25 of the output section 24, and the conductive film 27 of the comparison output section 26 were all gold films. The physical properties of each material were as follows: [Physical properties of YIG] Relative permittivity: 15.3 (dimensionless) Saturation magnetization: 1735 G Gyromagnetic constant (= gyromagnetic ratio): 2.8 MHz / Oe Damping constant: 1 x 10 －５ (Dimensionless) A bias magnetic field was applied to the YIG. Bias magnetic field: applied uniformly to the YIG in the z direction. Magnitude: 2335 Oe [Physical properties of gold] Electrical conductivity: 4.561 x 10 ７ S / m [Physical properties of copper] Conductivity: 5.96 x 10 ７ S / m

[0051] The insulating magnetic film 12 had a thickness of 10 μm, and the periodic conductive film 14 had a thickness of 2 μm. The constants d of the holes 15 and grooves 16 in the periodic conductive film 14 were 250 μm, g was 1 μm, and a was 450 μm. The dimensions of the input section 22, output section 24, and comparison output section 26 were D1: 2 mm, D2: 2 mm, and D3: 0.3 mm. The gold films on the input section 22, output section 24, and comparison output section 26 had a thickness of 30 nm. The width of the portion (spin-wave waveguide) formed between the input section 22 and output section 24 without a conductive film was 6 mm, and the bending angles α and β were 120°.

[0052] A spin wave was input to the input section 22 of the spin-wave waveguide structure 100 .

[0053] Figure 5 shows the results of measurements of spin waves propagating through the above structure, performed by installing microstrip antennas at both the input and output terminals and converting the magnetic field signals generated by the spin waves into electrical signals. The shade of color represents the spin wave intensity. The observed frequency is 1.8 GHz.

[0054] 6 shows the intensity distribution of the spin waves measured in the output unit 24 and the comparison output unit 26. The average value of the output unit 24 was 50 A / m, and the average value of the comparison output unit 26 was 15 A / m. It can be said that the spin waves were controlled to flow in the output unit 24.

[0055] [Comparative Example] For comparison, the state of spin waves when there is no periodic structure formed by the periodic conductive film 14 is shown in Figure 7. This is a structure without copper above or below the YIG. There is a YIG, and there are also gold films for the input and output terminals. All dimensions are the same. The bias magnetic field applied to the YIG and the frequency of the spin waves observed are also the same as in the example.

[0056] In the absence of a periodic structure, the spin waves input from the input section 22 of the input terminal have the largest component traveling in a straight line, increasing the intensity of the output section 26. At the same time, the spin waves spread during propagation, so they are reflected at the ends of the YIG and spread throughout the entire YIG.

[0057] [Evaluation of Examples and Comparative Examples] While the structure of the comparative example cannot restrict the direction of spin wave propagation, the periodic structure of the example restricts and controls the direction of spin wave propagation, allowing spin waves to be transmitted to the output section 24. This increases the strength of the output section 24. In other words, this example demonstrates that spin wave guidance can be achieved using a periodic structure. It is desirable to have both copper on the top and bottom of the YIG simultaneously. However, spin wave guidance is possible with only one of them. However, the example with copper films on both sides, as described above, has a better output ratio between the output section 24 and the comparative output section 26 than the example with only one side. In the example, the bending angle of the waveguide was 120°, but as mentioned above, it is also possible to fabricate waveguides with other angles. Furthermore, while the example uses a single waveguide, the structure of the present invention can also be applied to cases where a single waveguide is divided into three or more, as in Non-Patent Document 1.

[0058] Spin wave devices, which are expected to be the next generation of computing, require spin wave wiring technology. Because spin waves propagate through magnetic materials, conventional spin wave wiring methods involve shaping magnetic materials into wire-like shapes. This mimics the shape of electrical wiring in electronic devices. However, changing the shape of the magnetic material in spin wave devices, like that of electrical wiring, alters the magnetic properties unique to magnetic materials, known as shape magnetic anisotropy. This alters the spin wave propagation characteristics and significantly degrades propagation efficiency. This invention solves this problem by fabricating a periodic conductive structure above, below, or both the magnetic material and the wire, without changing the shape of the magnetic material. This method is expected to become the standard for spin wave wiring in spin wave devices in the near future.

[0059] The spin-wave waveguide structure of the present invention has the following effects on related fields.

[0060] (1) Computers: This will have a ripple effect on all fields currently using computers, including devices equipped with CPUs and other computing elements. It will be particularly useful in situations where computers are needed on the millimeter or micrometer scale. Examples include sensors and microchips that are being installed in mobile devices, wearable devices, and home appliances.

[0061] (2) High frequency, wireless, and communications fields Spin waves, like microwaves, are waves that respond on the order of GHz, but by converting them into waves that propagate through magnetic materials, their wavelengths can be shortened by more than 100 times. In terms of device (element) size, this means that the entire chip can be made 100 times smaller. Until now, analog high-frequency devices have not made much progress in miniaturization, and they are far from being portable. Therefore, the realization of spin wave devices is expected to lead to the miniaturization of high-frequency devices.

[0062] This specification includes the following aspects: [1]: A spin-wave waveguide structure for guiding spin waves, comprising: an insulating magnetic film; and a periodic conductor film arranged on at least one of both surfaces of the insulating magnetic film and made of a conductor film having a periodic structure, wherein the periodic structure of the periodic conductor film is formed by the conductor film being an assembly of a plurality of small film fragments, and the small film fragments are electrically insulated from adjacent small film fragments, and the electrical insulation of the small film fragments is achieved by separating the small film fragments by a plurality of holes and grooves connecting the plurality of holes, or by the presence of a nonmagnetic and nonconductive material in at least some of the holes and grooves, and the spin-wave waveguide structure has a portion on the insulating magnetic film having the periodic conductor film and a portion on the insulating magnetic film not having the conductor film, and the insulating magnetic film in the portion not having the conductor film functions as a spin-wave waveguide. [2]: The spin-wave waveguide structure of the above [1], wherein the insulating magnetic film is made of magnetic garnet. [3]: The spin-wave waveguide structure of the above [2], wherein the insulating magnetic film is made of yttrium iron garnet. [4]: ​​The spin-wave waveguide structure of any of the above [1] to [3], wherein the conductive film contains at least one of copper, aluminum, gold, silver, platinum, iron, a transparent conductor, a superconductor, graphene, carbon nanotubes, an organic conductive material, and a conductive magnetic material. [5]: The spin-wave waveguide structure of any of the above [1] to [4], wherein the insulating magnetic film has a thickness of 1 mm or less. [6]: The spin-wave waveguide structure of any of the above [1] to [5], wherein the conductive film has a thickness of 100 μm or less. [7]: The spin-wave waveguide structure according to any one of [1] to [6], further comprising a support substrate, wherein the insulating magnetic film and the periodic conductive film are disposed on the support substrate. [8]: The spin-wave waveguide structure according to [7], wherein the support substrate is at least one of a silicon substrate, a glass substrate, a garnet substrate, a dielectric substrate, a conductive substrate, an insulating substrate, a magnetic substrate, a non-magnetic substrate, a wood substrate, and a stone substrate.[9]: The spin-wave waveguide structure according to [7] or [8] above, wherein the thickness of the support substrate is 100 μm or more and 500 μm or less.

[10] : The spin-wave waveguide structure according to any one of [1] to [9] above, wherein a spin-wave input section and an output section are formed in the insulating magnetic film in a portion not having the conductive film.

[0063] The present invention is not limited to the above-described embodiments, which are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and that provides similar effects is included within the technical scope of the present invention.

Claims

1. A spin-wave waveguide structure for guiding spin waves, comprising: an insulating magnetic film; and a periodic conductor film consisting of a conductor film having a periodic structure arranged on at least one of both surfaces of the insulating magnetic film, wherein the periodic structure of the periodic conductor film is such that the conductor film is composed of an assembly of a plurality of small film pieces, and the small film pieces are electrically insulated from adjacent small film pieces, and the small film pieces are electrically insulated from each other by separating the small film pieces by a plurality of holes and grooves connecting the plurality of holes, or by the presence of a nonmagnetic and nonconductive material in at least some of the holes and grooves, and wherein the spin-wave waveguide structure has a portion on the insulating magnetic film having the periodic conductor film, and a portion on the insulating magnetic film not having the conductor film, and the insulating magnetic film in the portion not having the conductor film functions as a spin-wave waveguide.

2. The spin wave guide structure according to claim 1, wherein the insulating magnetic film is made of magnetic garnet.

3. The spin wave guide structure according to claim 2, wherein the insulating magnetic film is made of yttrium iron garnet.

4. The spin wave waveguide structure according to claim 1, characterized in that the conductive film contains at least one of copper, aluminum, gold, silver, platinum, iron, transparent conductors, superconductors, graphene, carbon nanotubes, organic conductive materials, and conductive magnetic materials.

5. The spin wave guide structure according to claim 1, wherein the insulating magnetic film has a thickness of 1 mm or less.

6. The spin-wave waveguide structure according to claim 1, wherein the thickness of the conductive film is 100 μm or less.

7. The spin wave guide structure according to any one of claims 1 to 6, further comprising a support substrate, the insulating magnetic film and the periodic conductive film being disposed on the support substrate.

8. The spin wave guide structure according to claim 7, wherein the support substrate is at least one of a silicon substrate, a glass substrate, a garnet substrate, a dielectric substrate, a conductive substrate, an insulating substrate, a magnetic substrate, a non-magnetic substrate, a wood substrate, and a stone substrate.

9. The spin-wave waveguide structure according to claim 7, wherein the thickness of the support substrate is 100 μm or more and 500 μm or less.

10. The spin wave waveguide structure according to claim 1, wherein an input section and an output section for a spin wave are formed in the insulating magnetic film in a portion not having the conductive film.

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