Antenna and method for regulating the same, electronic device

Abstract

An antenna and a method for regulating the same, and an electronic device. The antenna comprises a piezoelectric layer and a magnetic layer arranged in a stack, and further comprises an electrode structure arranged on at least one surface of the piezoelectric layer, the electrode structure being configured to receive an alternating voltage to excite the piezoelectric layer to generate acoustic resonances, a plurality of acoustic resonance modes being formed in the piezoelectric layer and the magnetic layer, frequencies of the plurality of acoustic resonance modes being discretely distributed in a working frequency band, and constituting a phonon frequency comb; the magnetic layer being configured to be controlled to generate a magnon mode matching a frequency of a target acoustic resonance mode in the plurality of acoustic resonance modes, so that the magnon mode and the target acoustic resonance mode are strongly coupled, a backcrossing phenomenon is avoided in a frequency-magnetic field spectrum, a magnon-phonon hybrid mode is formed, and electromagnetic radiation is realized. The antenna is realized as a magnon-phonon strongly coupled antenna with a phonon frequency comb, the antenna can realize electromagnetic radiation for excitation of precession of a dynamic magnetic moment at a scale of one hundredth of a wavelength of electromagnetic waves, and the radiation frequency is adjustable.

Description

Technical Field

[0001] Embodiments of this disclosure relate to an antenna and its control method, as well as an electronic device. Background Technology

[0002] Miniature antennas are much smaller than the wavelength in free space, resulting in weak radiation capabilities and making it difficult to achieve effective electromagnetic radiation.

[0003] Based on the radiation mechanism, acoustically excited antennas utilize the acoustic resonance of an acoustic resonator to replace electromagnetic resonance, achieving effective radiation at scales smaller than one-hundredth of the electromagnetic wave wavelength. This offers significant advantages over traditional electrical antennas of the same size. Therefore, acoustically excited antennas, to some extent, fill the gap in electrically small antennas with radiating dimensions smaller than one-hundredth of the electromagnetic wave wavelength. Summary of the Invention

[0004] At least one embodiment of this disclosure provides an antenna comprising a stacked piezoelectric layer and a magnetic layer, and an electrode structure disposed on at least one surface of the piezoelectric layer. The electrode structure is configured to receive an alternating voltage to excite the piezoelectric layer to generate acoustic resonance, forming a plurality of acoustic resonance modes in the piezoelectric layer and the magnetic layer. The frequencies of the plurality of acoustic resonance modes are discretely distributed in the operating frequency band, forming a phonon frequency comb. The magnetic layer is configured to controllably generate a magnon mode whose frequency matches that of a target acoustic resonance mode among the plurality of acoustic resonance modes, so that the magnon mode coherently couples with the target acoustic resonance mode, generating an avoidance crossover phenomenon in the frequency-magnetic field spectrum, forming a magnon-phonon hybrid mode, and realizing electromagnetic radiation.

[0005] For example, in the antenna provided in at least one embodiment of this disclosure, the thickness of the piezoelectric layer is d. e ,but: , Among them, C D The piezoelectric stress constant of the piezoelectric layer is... ρ e f0 is the piezoelectric material density of the piezoelectric layer, f0 is the center frequency, the operating frequency band is f1~f2, and f0 = (f1 + f2) / 2.

[0006] For example, in at least one embodiment of the antenna provided in this disclosure, the thickness of the magnetic layer is d. m ,but: , Among them, C H The constant magnetic field stiffness coefficient of the magnetic layer is given. ρ mThe magnetic material density of the magnetic layer is given, Δf is the frequency interval of the phonon frequency comb, and within the operating frequency band, the number of the plurality of acoustic resonant modes is N, where f1-f2=N. Δf, where N is a positive integer greater than or equal to 2.

[0007] For example, in at least one embodiment of the antenna provided in this disclosure, the thickness of the magnetic layer is greater than the thickness of the piezoelectric layer.

[0008] For example, in an antenna provided in at least one embodiment of this disclosure, the magnetic layer is configured to: generate a first magnetic resonant mode under the control of a first magnetic field that matches a first frequency of a first target acoustic resonant mode among the plurality of acoustic resonant modes, so that the first magnetic resonant mode is coupled with the first target acoustic resonant mode to form a first magnetic resonant-phonon hybrid mode, thereby realizing a first electromagnetic radiation state; and generate a second magnetic resonant mode under the control of a second magnetic field that matches a second frequency of a second target acoustic resonant mode among the plurality of acoustic resonant modes, so that the second magnetic resonant mode is coupled with the second target acoustic resonant mode to form a second magnetic resonant-phonon hybrid mode, thereby realizing a second electromagnetic radiation state.

[0009] For example, in an antenna provided in at least one embodiment of this disclosure, the surface of the piezoelectric layer away from the magnetic layer is a first surface, and the surface close to the magnetic layer is a second surface. The electrode structure includes a first electrode and a second electrode, which are disposed at intervals on the first surface. The second surface is in direct contact with the magnetic layer. Alternatively, the first electrode is disposed on the first surface, and the second electrode is disposed in a first region of the second surface. The second electrode is in direct contact with the magnetic layer, and a second region of the second surface other than the first region is in direct contact with the magnetic layer.

[0010] At least one embodiment of this disclosure provides an electronic device that includes an antenna provided in an embodiment of this disclosure.

[0011] At least one embodiment of this disclosure also provides a method for controlling an antenna, the antenna including a piezoelectric layer and a magnetic layer stacked together, and an electrode structure disposed on at least one surface of the piezoelectric layer. The method includes: applying an alternating voltage to the electrode structure to excite the piezoelectric layer to generate acoustic resonance, forming a plurality of acoustic resonance modes in the piezoelectric layer and the magnetic layer, the frequencies of the plurality of acoustic resonance modes being discretely distributed in the operating frequency band to form a phonon frequency comb; applying a magnetic field to the magnetic layer to generate a magnon mode whose frequency matches that of a target acoustic resonance mode among the plurality of acoustic resonance modes, so that the magnon mode is coherently coupled with the target acoustic resonance mode, generating an avoidance crossover phenomenon in the frequency-magnetic field spectrum, forming a magnon-phonon hybrid mode, and realizing electromagnetic radiation.

[0012] For example, at least one embodiment of this disclosure provides an antenna control method in which a magnetic field is applied to the magnetic layer to generate a magnetic resonant mode whose frequency matches that of a target acoustic resonant mode among a plurality of acoustic resonant modes. This includes: applying a magnetic field with a first magnetic field strength to the magnetic layer to generate a first magnetic resonant mode whose frequency matches that of a first target acoustic resonant mode among the plurality of acoustic resonant modes; coupling the first magnetic resonant mode with the first target acoustic resonant mode to form a first magnetic resonant-phonon hybrid mode, thereby achieving a first electromagnetic radiation state; and applying a magnetic field with a second magnetic field strength to the magnetic layer to generate a second magnetic resonant mode whose frequency matches that of a second target acoustic resonant mode among the plurality of acoustic resonant modes; coupling the second magnetic resonant mode with the second target acoustic resonant mode to form a second magnetic resonant-phonon hybrid mode, thereby achieving a second electromagnetic radiation state.

[0013] For example, at least one embodiment of this disclosure provides an antenna control method in which a magnetic field is applied to the magnetic layer, including: placing the antenna between a first magnetic generating device and a second magnetic generating device that are arranged opposite each other along an axis, and the angle between the surface of the antenna and the axis is 40 degrees to 50 degrees.

[0014] For example, at least one embodiment of this disclosure provides an antenna control method, the control method further comprising: adjusting the magnitude of the alternating voltage to adjust the intensity of the electromagnetic radiation. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings of the embodiments will be briefly described below. Obviously, the drawings described below only relate to some embodiments of this disclosure and are not intended to limit this disclosure.

[0016] Figure 1 This is a partial cross-sectional schematic diagram of an antenna provided for at least one embodiment of the present disclosure.

[0017] Figure 2 This is a schematic diagram illustrating the effect of strong magnetoron-phonon coupling achieved by an antenna provided in at least one embodiment of this disclosure.

[0018] Figure 3 A partial frequency distribution diagram of the phonon frequency comb formed by the antenna provided in at least one embodiment of this disclosure.

[0019] Figure 4 The frequency-magnetic field spectrum formed by the antenna is provided in at least one embodiment of this disclosure.

[0020] Figure 5The electromagnetic radiation intensity map is generated by the magnetoron-phonon hybrid mode excited by the antenna provided in at least one embodiment of this disclosure under the bias of an external magnetic field.

[0021] Figure 6 This is a schematic diagram of a planar structure of another antenna provided for at least one embodiment of the present disclosure.

[0022] Figure 7 It shows Figure 6 A schematic diagram of the cross-section of the antenna along line AA.

[0023] Figure 8 This is a diagram showing the arrangement of the electrode structure of an antenna according to at least one embodiment of the present disclosure.

[0024] Figure 9 This is a schematic diagram of another antenna planar structure provided for at least one embodiment of the present disclosure.

[0025] Figure 10 It shows Figure 9 A schematic diagram of the cross-section of the antenna along line BB.

[0026] Figure 11 This is a schematic diagram of applying a magnetic field to a magnetic layer in an antenna control method provided in at least one embodiment of the present disclosure. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0028] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as “comprising” or “including” mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as “connected” or “linked” are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as “upper,” “lower,” “left,” and “right” are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described objects changes.

[0029] The inventors of this disclosure discovered in their research that in conventional megahertz to gigahertz acoustically excited magnetoelectric antennas, the magnetoron and phonon are in a simple quasi-static strain coupling state, which has limited driving capability for the magnetic moment, resulting in weak radiation performance. Furthermore, conventional ultra-high frequency (UHF) band acoustically excited antennas can usually only operate near a fixed acoustic resonant frequency, making it difficult to achieve the required radiation frequency adjustment.

[0030] For example, in an acoustically driven magneto-electro-mechanical antenna, the radiation source it relies on is quasi-static stress coupling, meaning the coupling between phonons and magnons is in the non-coupling region. When the magnon and phonon modes are far apart, the effect of acoustic stress on the magnetic layer mainly manifests as stress-induced quasi-static magnetic moment oscillation. At this time, the magnetic moment response is mainly driven by external acoustic stress, the amplitude of magnetic moment movement is small, and the conversion efficiency between acoustic energy and magnetic dynamic energy in the magnetic layer is extremely low.

[0031] For example, in a magneto-electro-mechanical antenna based on adjusting the ferromagnetic resonance frequency using a magnetic field, the radiation frequency is determined by a single acoustic resonant frequency and cannot be adjusted.

[0032] In response, at least one embodiment of this disclosure provides an antenna and its control method. The antenna includes a piezoelectric layer and a magnetic layer stacked together, and an electrode structure disposed on at least one surface of the piezoelectric layer. The electrode structure is configured to receive an alternating voltage to excite the piezoelectric layer to generate acoustic resonance, forming multiple acoustic resonance modes in the piezoelectric layer and the magnetic layer. The frequencies of the multiple acoustic resonance modes are discretely distributed in the operating frequency band, forming a phonon frequency comb. The magnetic layer is configured to controllably generate a magnon mode whose frequency matches that of a target acoustic resonance mode among the multiple acoustic resonance modes, so that the magnon mode is coherently coupled with the target acoustic resonance mode, generating an avoidance crossover phenomenon in the frequency-magnetic field spectrum, forming a magnon-phonon hybrid mode, and realizing electromagnetic radiation.

[0033] Therefore, the antenna provided in this embodiment can be implemented as a micro antenna with strong phonon-magnetic coupling and a phonon frequency comb. By tuning the magnetic layer, the magnetic resonant mode generated by the magnetic layer can be strongly coupled with different acoustic resonant modes in the phonon frequency comb under different magnetic field conditions. This allows the stress-driven magnetic moment motion to evolve from quasi-static oscillation to high-efficiency coherent precession with controllable frequency, thereby realizing a multi-frequency radiating micro antenna with high radiation frequency controlled by a magnetic field. This antenna can realize electromagnetic radiation excited by the precession of the dynamic magnetic moment at a scale of one-hundredth of the electromagnetic wave wavelength, and the radiation frequency can be adjusted within a large operating frequency band.

[0034] The antenna, its control method, and electronic device disclosed herein will be described below through several specific embodiments.

[0035] This disclosure provides an antenna in at least one embodiment. Figure 1 A schematic diagram of the cross-sectional structure of the antenna is shown, as follows. Figure 1 As shown, the antenna includes a piezoelectric layer 10 and a magnetic layer 20 stacked together, and also includes an electrode structure 30 disposed on at least one surface of the piezoelectric layer 10.

[0036] The electrode structure 30 is configured to receive alternating voltage to excite the piezoelectric layer 10 to generate acoustic resonance, forming multiple acoustic resonance modes in the piezoelectric layer 10 and the magnetic layer 20. The frequencies of the multiple acoustic resonance modes are discretely distributed in the operating frequency band, forming a phonon frequency comb. The magnetic layer 20 is configured to controllably generate a magnetic resonant mode that matches the frequency of the target acoustic resonance mode among the multiple acoustic resonance modes, so that the magnetic resonant mode is coherently coupled with the target acoustic resonance mode, generating an avoidance crossover phenomenon in the frequency-magnetic field spectrum, forming a magnetic resonant-phonon hybrid mode, and realizing electromagnetic radiation.

[0037] For example, in the antenna provided in this embodiment, the piezoelectric layer 10 and the magnetic layer 20 constitute a magnetoelectric heterojunction. Excited by the alternating voltage of the electrode structure 30, multiple high-overtone acoustic resonant modes are formed in the magnetoelectric heterojunction. The frequencies of these multiple high-overtone acoustic resonant modes are discretely distributed within the operating frequency band, forming a phonon frequency comb. A low-loss magnetic layer provides a magnetic resonator mode, enabling the magnetic resonator mode to be frequency-matched with a selected high-overtone acoustic resonator mode (as the target acoustic resonator mode) among the multiple high-overtone acoustic resonant modes, thus achieving effective magnetoelastic coupling. At this time, an external magnetic field can be used to adjust the frequency position of the magnetic resonator mode in the magnetic layer, allowing the magnetic resonator mode to sequentially match different frequencies in the phonon frequency comb. When the magnetic resonator mode and the target acoustic resonator mode achieve coherent strong coupling, a magneto-phonon hybrid mode is formed. In this hybrid mode, acoustic stress no longer causes only quasi-static oscillation of the magnetic moment along a certain direction (e.g., Figure 2 (As shown in the "quasi-static coupling" on the left), instead, it continuously drives the magnetization vector to precess coherently and efficiently around its equilibrium direction, such as... Figure 2 As shown by the "strong coupling" on the right, this enables efficient electromagnetic radiation.

[0038] As can be seen, in the above antenna, the magnetic field is adjusted to regulate the magnetic resonator modes in the magnetic layer 20, while the phonon frequency comb is generated by and remains unchanged by the piezoelectric layer 10 and the magnetic layer 20 themselves. Therefore, by changing the magnetic field state, different radiation modes corresponding to different frequencies in the phonon frequency comb can be selected without changing the structure of the piezoelectric layer 10 and the magnetic layer 20 themselves.

[0039] For example, such as Figure 1 As shown, the thickness of the piezoelectric layer 10 is d. e ,but: , Among them, C DThe piezoelectric stress constant of piezoelectric layer 10 is expressed in Pa. ρ e Density of the piezoelectric material in piezoelectric layer 10, in kg / m³ 3 f0 is the center frequency, in Hz, and the operating frequency band is f1~f2. The center frequency f0 = (f1 + f2) / 2. Therefore, given the material of the piezoelectric layer 10, C D and ρ e The thickness d of the piezoelectric layer 10 is determined. e It is related to the center frequency f0.

[0040] For example, the acoustic resonance mode formed by the piezoelectric layer 10 under the excitation of alternating voltage can be a surface acoustic wave mode, such as a horizontal shear wave mode, a Rayleigh wave mode, a Leff wave mode, etc., or a bulk acoustic wave mode, such as a Lamb wave mode, a thickness stretching bulk acoustic wave mode, a thickness shearing bulk acoustic wave mode, an axial mode, a length stretching mode, etc. The embodiments disclosed herein do not specifically limit this.

[0041] For example, such as Figure 1 As shown, the thickness of the magnetic layer 20 is d. m ,but: , Among them, C H This is the constant magnetic field stiffness coefficient of magnetic layer 20, in Pa. ρ m The density of the magnetic material in magnetic layer 20 is expressed in kg / m³. 3 Δf is the frequency spacing of the phonon frequency comb, in Hz; within the operating frequency band, the number of multiple acoustic resonant modes is N, f2-f1=N. Δf, N are positive integers greater than or equal to 2. Therefore, given the material of magnetic layer 20, C H and ρ m For determination, the thickness d of the magnetic layer 20 m It is related to the frequency interval Δf of the phonon frequency comb.

[0042] For example, in some embodiments, in order to achieve the desired phonon frequency comb, the thickness of the magnetic layer 20 is greater than the thickness of the piezoelectric layer 10; for example, the thickness of the magnetic layer 20 is much greater than the thickness of the piezoelectric layer 10. For example, the thickness of the magnetic layer 20 is more than 10 times, more than 50 times, or even more than 100 times the thickness of the piezoelectric layer 10.

[0043] For example, in one example, the operating frequency band is 2GHz-3.5GHz, and the material of the piezoelectric layer 10 is aluminum nitride (AlN). In this case, the thickness of the piezoelectric layer 10 is approximately 900nm-1.5μm. With a target frequency interval Δf of 9MHz, the material of the magnetic layer 20 is yttrium iron garnet (YIG), and the thickness of the magnetic layer 20 is approximately 250μm to 350μm, for example, approximately 300μm. In this example, the thickness of the magnetic layer 20 is more than 100 times the thickness of the piezoelectric layer 10.

[0044] For example, the aforementioned 2GHz-3.5GHz frequency coverage can meet the needs of near-field communication such as Bluetooth; or it can meet the needs of wireless communication such as fourth-generation mobile communication systems (4G). In some examples, through structural design, even higher frequency band coverage can be achieved, such as meeting the needs of fifth-generation mobile communication systems (5G).

[0045] For example, in some embodiments, the magnetic layer 20 is configured to: generate a first magnetic resonant mode under the control of a first magnetic field that matches a first frequency of a first target acoustic resonant mode among a plurality of acoustic resonant modes, so that the first magnetic resonant mode is coupled with the first target acoustic resonant mode to form a first magnetic resonant-phonon hybrid mode, thereby realizing a first electromagnetic radiation state; and generate a second magnetic resonant mode under the control of a second magnetic field that matches a second frequency of a second target acoustic resonant mode among a plurality of acoustic resonant modes, so that the second magnetic resonant mode is coupled with the second target acoustic resonant mode to form a second magnetic resonant-phonon hybrid mode, thereby realizing a second electromagnetic radiation state.

[0046] For example, the magnetic layer 20 is also configured to: generate a third magnetic resonant mode under the control of a third magnetic field that matches the third frequency of a third target acoustic resonant mode among a plurality of acoustic resonant modes, so that the third magnetic resonant mode couples with the third target acoustic resonant mode to form a third magnetic resonant-phonon hybrid mode and realize a third electromagnetic radiation state; and generate a fourth magnetic resonant mode under the control of a fourth magnetic field that matches the fourth frequency of a fourth target acoustic resonant mode among a plurality of acoustic resonant modes, so that the fourth magnetic resonant mode couples with the fourth target acoustic resonant mode to form a fourth magnetic resonant-phonon hybrid mode and realize a fourth electromagnetic radiation state, etc.

[0047] Therefore, under different magnetic field control, the antenna can generate different oscillator-phonon hybrid modes, realize strong coupling between the magnetic oscillator mode and the acoustic resonant mode at different frequencies, so as to achieve different electromagnetic radiation effects and realize adjustable radiation effects.

[0048] In the embodiments of this disclosure, the operating frequency band of the antenna refers to the frequency range covered by the phonon frequency comb, such as the resonant frequencies corresponding to the fundamental mode and higher-order modes of the surface acoustic wave resonant mode or the bulk acoustic wave resonant mode.

[0049] For example, setting the operating frequency band to f1~f2, after the electrode structure 30 receives an alternating voltage (e.g., a high-frequency alternating voltage), the alternating voltage is applied to the piezoelectric material of the piezoelectric layer 10. The piezoelectric layer 10 generates strain through the inverse piezoelectric effect and couples to the magnetic layer 20. Within the operating frequency band of f1-f2, the piezoelectric layer 10 and the magnetic layer 20 form N acoustic resonant modes, such as higher-order overtone shear acoustic resonant modes; there is a frequency interval of approximately Δf between each pair of adjacent acoustic resonant modes, and the N adjacent acoustic resonant modes together constitute a phonon frequency comb, f1-f2 = N. Δf.

[0050] For example, taking an antenna formed by electrode structure 30 being made of aluminum (Al), piezoelectric layer 10 being made of aluminum nitride (AlN), and magnetic layer 20 being made of yttrium iron garnet (YIG) as an example, the piezoelectric layer 10 and magnetic layer 20 constitute a high-order overtone acoustic resonator. Figure 3 The diagram shows a partial frequency distribution of the phonon frequency comb formed by the antenna, with the horizontal axis representing frequency f (GHz) and the vertical axis representing the reflection coefficient S. 11 (dB). For example Figure 3 As shown, each pair of adjacent acoustic resonant modes in the multiple acoustic resonant modes has the same frequency interval.

[0051] By changing the magnetic field state of the magnetic layer 20, the frequency of the magnetic resonator mode in the magnetic layer 20 can be adjusted; when the magnetic resonator mode approaches the frequency f1~f2 within the operating frequency band... 01 f 02 and f 03 When different acoustic resonant modes are nearby, the magnetic resonator mode couples with the corresponding acoustic resonant mode, resulting in multiple avoidance crossover phenomena in the frequency-magnetic field spectrum, such as... Figure 4 As shown.

[0052] For example, Figure 4 The frequency-magnetic field spectrum formed by the above antenna is shown, where the horizontal axis represents the magnetic field H0 (Oe), and the vertical axis represents the frequency f (GHz) and the reflection coefficient S. 11 (1) It shows the change of strong coupling between magnon and phonon with the magnetic field bias strength. It can be seen that by changing the magnetic field, the coupling of different acoustic resonant modes of magnon mode and phonon frequency comb can be achieved.

[0053] For example, the acoustic resonant mode corresponding to each frequency in the phonon frequency comb can be used as a target acoustic resonant mode. This can be achieved by adjusting the magnetic field to form a corresponding magnon mode, which in turn forms a magnon-phonon hybrid mode. Since each hybrid mode contains a dynamic magnetization component, the frequency of each target acoustic resonant mode can generate an electromagnetic radiation response.

[0054] For example, in the first magnetic field state, the magnon mode approaches the first frequency f in the phonon frequency comb. 01 When the acoustic resonant mode is in the first frequency f, the magnon mode is strongly coupled with the acoustic resonant mode, forming the first magnon-phonon hybrid mode. 01 A first radiation response is generated at the point; under the second magnetic field state, the magnon mode approaches the second frequency f in the phonon frequency comb. 02 The acoustic resonant mode is strongly coupled with this acoustic resonant mode, at which point the magnetic moment efficiently precesses and transfers to the second frequency f. 02 The corresponding magnon-phonon hybrid mode, at the second frequency f 02 A second radiation response is generated at the magnetic layer 20; similarly, the magnetic resonant mode can sequentially form a one-to-one correspondence or a preset correspondence with the acoustic resonant mode of different frequencies under different magnetic field states. Thus, different electromagnetic radiations can be generated by adjusting the magnetic field state of the magnetic layer 20.

[0055] For example, Figure 5 The diagram shows the electromagnetic radiation intensity generated by the magnon-phonon hybrid mode excited by the above antenna under an external magnetic field bias of 420.1 Oe. The horizontal axis represents the frequency f (GHz), and the vertical axis represents the radiation intensity h. x (A / m); such as Figure 5 As shown, under an external magnetic field bias of 420.1 Oe, the intensity of electromagnetic radiation corresponding to the excited magnon-phonon hybrid mode at a frequency of 2.678 GHz is enhanced by more than 20 dB (approximately 100 times the radiation efficiency) compared to out-of-band radiation (i.e., electromagnetic radiation without the magnon-phonon hybrid mode). This demonstrates that by forming a magnon-phonon hybrid mode through strong coupling between the magnon mode and the acoustic resonant mode, acoustic stress no longer merely causes quasi-static oscillation of the magnetic moment along a certain direction, but continuously drives the magnetization vector to precess coherently and efficiently around its equilibrium direction, thereby achieving highly efficient electromagnetic radiation.

[0056] The antenna provided in this embodiment can be implemented as a deep subwavelength micro antenna. By combining the strong coupling mechanism of magnon-phonon with a high overtone phonon frequency comb, the acoustic stress can drive the magnetic moment to generate high-efficiency coherent precession under strong coupling. Different phonon frequencies can be selected as radiation frequencies by using an external magnetic field, thereby simultaneously achieving radiation enhancement and multi-frequency tunability.

[0057] As can be seen, compared with traditional acoustic wave-driven magnetoelectric antennas operating in uncoupled or weakly coupled regions and antennas with only a single radiation mode, the antenna provided in this disclosure can achieve the following better technical effects: 1) Significantly improve the dynamic magnetic moment amplitude and electromagnetic radiation intensity within the same size, for example, by 1-2 orders of magnitude; 2) Achieve multiple selectable radiation frequencies in a single micro-antenna device through an external magnetic field, realizing frequency switching without structural modifications; 3) Reduce the use of multi-antenna combinations, external matching networks, and RF switching circuits; 4) Improve the product's integration, reconfigurability, and application scenario adaptability, making the antenna provided in this disclosure widely applicable to fields such as micro wireless communication, frequency coding, tunable microwave transmission, and on-chip RF systems.

[0058] For example, in some embodiments, the electrode structure 30 can be designed differently, as long as it can effectively apply an alternating voltage to the piezoelectric layer 10.

[0059] For example, Figure 6 This diagram illustrates a planar structure of another antenna provided in at least one embodiment of the present disclosure. Figure 7 It shows Figure 6 A schematic diagram of the antenna's cross-section along line AA, as shown in the image. Figure 6 and Figure 7 As shown, the surface of the piezoelectric layer 10 furthest from the magnetic layer 20 is the first surface S1, and the surface closest to the magnetic layer 20 is the second surface S2. The electrode structure 30 includes a first electrode 31 and a second electrode 32, which are spaced apart on the first surface S1, and the second surface S2 is in direct contact with the magnetic layer 20. The first electrode 31 and the second electrode 32 are respectively connected to a power source to receive alternating voltage. At this time, the first electrode 31 and the second electrode 32 form a transverse electrode structure, which can be controlled to form an in-plane electric field to excite the piezoelectric layer 10.

[0060] For example, in Figure 6 and Figure 7 In the example, the planar shape of the first electrode 31 and the second electrode 32 is rectangular; in other examples, such as... Figure 8 As shown, the first electrode 31 and the second electrode 32 can also be in the form of interdigitated electrodes. The specific arrangement of the first electrode 31 and the second electrode 32 is not limited in the embodiments of this disclosure.

[0061] For example, Figure 9 This diagram illustrates a planar structure of another antenna provided in at least one embodiment of the present disclosure. Figure 10 It shows Figure 9 A schematic diagram of the antenna's cross-section along line BB, as shown in the image. Figure 9 and Figure 10As shown, the surface of the piezoelectric layer 10 furthest from the magnetic layer 20 is the first surface S1, and the surface closest to the magnetic layer 20 is the second surface S2. The electrode structure 30 includes a first electrode 31 and a second electrode 32. The first electrode 31 is disposed on the first surface S1, and the second electrode 32 is disposed in a first region S21 of the second surface S2. The second electrode 32 is in direct contact with the magnetic layer 20, and a second region S22 of the second surface S2, excluding the first region S21, is also in direct contact with the magnetic layer 20. The first electrode 31 and the second electrode 32 are respectively connected to a power source to receive alternating voltage. At this time, the first electrode 31 and the second electrode 32 form a vertical electrode structure, which can be controlled to form a vertical electric field to excite the piezoelectric layer 10.

[0062] For example, the material of electrode structure 30 includes metallic or alloy materials such as titanium (Ti), aluminum (Al), nickel (Ni), copper (Cu), platinum (Pt), gold (Au), or silver (Ag). The embodiments of this disclosure do not specifically limit the material of electrode structure 30.

[0063] Since the piezoelectric layer 10 is anisotropic, its piezoelectric material has different voltage coefficients in different directions. Depending on the different piezoelectric materials, different electrode arrangements can be selected to achieve the desired excitation effect.

[0064] For example, the resonator structure formed by the piezoelectric layer 10, the magnetic layer 20, and the electrode structure 30, capable of exciting an acoustic frequency comb, can be a surface acoustic wave resonator based on interdigitated electrodes, a thin-film bulk acoustic wave resonator, a solid-assembly acoustic wave resonator, a nanoplate resonator, a laterally excited bulk acoustic wave resonator, or a higher-order overtone bulk acoustic wave resonator (see reference). Figure 9 and Figure 10 ), and laterally excited high-order overtone acoustic resonators (reference) Figure 6 and Figure 7 Examples of such embodiments are not specifically limited in this respect.

[0065] For example, the piezoelectric material of the piezoelectric layer 10 can be a bulk piezoelectric material, including lithium niobate (LiNbO3) with different orientations, lithium tantalate (LiTaO3) with different orientations, potassium dihydrogen phosphate (KDP), lead zirconate titanate (PZT), lead magnesium niobate-lead titanate (PMN-PT), or quartz, etc.; or, the piezoelectric material can be a piezoelectric thin film bonded or directly grown on a substrate, the material of the piezoelectric thin film including lithium niobate (LiNbO3) with different orientations, lithium tantalate (LiTaO3) with different orientations, aluminum nitride (AlN), zinc oxide (ZnO), gallium nitride (GaN), or lead zirconate titanate (PZT), etc., and the material of the substrate used to support the piezoelectric thin film includes silicon (Si), silicon oxide (SiO), silicon carbide (SiC), silicon nitride (SiN), diamond, or sapphire, etc.; the embodiments of this disclosure do not specifically limit the material of the piezoelectric layer 10.

[0066] For example, the material of the magnetic layer 20 can be a magnetic thin film or single crystal bonded or grown directly on the substrate, including yttrium iron garnet (YIG), nickel (Ni), iron (Fe), iron gallium (FeGa), iron gallium boron (FeGaB), metallic glass (Metglas), etc.; the embodiments of this disclosure do not specifically limit the material of the magnetic layer 20.

[0067] At least one embodiment of this disclosure provides an electronic device that includes an antenna provided in an embodiment of this disclosure.

[0068] For example, the electronic device may also include a signal application circuit configured to apply an alternating voltage to the electrode structure 30. This signal application circuit may include modules such as signal generation, power amplification, filters, and baseband chips.

[0069] For example, the electronic device can be an on-chip fully integrated wireless transceiver module, which can be applied to devices limited by antenna size, such as mobile devices (e.g., smartphones, tablets, and wearable devices), IoT devices, and implantable medical devices (e.g., pacemakers, neurostimulators), to achieve high-intensity radiation and frequency tunability at a scale of 1 / 100 of the electromagnetic wave wavelength.

[0070] At least one embodiment of this disclosure also provides a method for controlling an antenna, referencing Figure 1The antenna includes a piezoelectric layer 10 and a magnetic layer 20 stacked together, and an electrode structure 30 disposed on at least one surface of the piezoelectric layer 10. The control method includes: applying an alternating voltage to the electrode structure 30 to excite the piezoelectric layer 10 to generate acoustic resonance, forming multiple acoustic resonance modes in the piezoelectric layer 10 and the magnetic layer 20, the frequencies of the multiple acoustic resonance modes being discretely distributed in the operating frequency band to form a phonon frequency comb; applying a magnetic field to the magnetic layer 20 to generate a magnon mode whose frequency matches that of a target acoustic resonance mode among the multiple acoustic resonance modes, so that the magnon mode is coherently coupled with the target acoustic resonance mode, generating an avoidance crossover phenomenon in the frequency-magnetic field spectrum, forming a magnon-phonon hybrid mode, and realizing electromagnetic radiation.

[0071] For example, in some embodiments, applying a magnetic field to the magnetic layer 20 to generate a magnetic resonant mode whose frequency matches that of a target acoustic resonant mode among a plurality of acoustic resonant modes includes: applying a magnetic field with a first magnetic field strength to the magnetic layer 20 to generate a first magnetic resonant mode whose frequency matches that of a first target acoustic resonant mode among a plurality of acoustic resonant modes, thereby coupling the first magnetic resonant mode with the first target acoustic resonant mode to form a first magnetic resonant-phonon hybrid mode and achieving a first electromagnetic radiation state; and applying a magnetic field with a second magnetic field strength to the magnetic layer 20 to generate a second magnetic resonant mode whose frequency matches that of a second target acoustic resonant mode among a plurality of acoustic resonant modes, thereby coupling the second magnetic resonant mode with the second target acoustic resonant mode to form a second magnetic resonant-phonon hybrid mode and achieving a second electromagnetic radiation state.

[0072] Of course, applying a magnetic field to the magnetic layer 20 may also include applying a magnetic field with a third magnetic field strength to the magnetic layer 20, applying a magnetic field with a fourth magnetic field strength to the magnetic layer 20, etc., so that the formed magnetic resonator mode is coupled with acoustic resonant modes of different frequencies. The magnetic field can be adjusted according to the specific needs.

[0073] For example, in some embodiments, such as Figure 11 As shown, applying a magnetic field to the magnetic layer 20 includes: placing the antenna 100 between the first magnetic generating device 41 and the second magnetic generating device 42, which are arranged opposite each other along the axis X, and the angle α between the surface of the antenna 100 and the axis X is 40 degrees to 50 degrees, for example, 45 degrees.

[0074] Since the direction of the bias magnetic field directly affects the direction of the spin precession of the magnetic particles in the magnetic material of the magnetic layer 20, it also affects the interaction between the magnetic resonant mode and the phonon mode. The bias magnetic field formed by the first magnetic generating device 41 and the second magnetic generating device 42 is parallel to the plane where the magnetic layer 20 is located. The bias magnetic field forms a predetermined azimuth angle, i.e., angle α, in this plane relative to the predetermined crystal axis, the shear strain direction, or the extension direction of the electrode structure 30. At the above angle α, the strongest magnetic resonant mode-phonon mode coupling can be achieved, thereby obtaining the best radiation effect.

[0075] For example, the first magnetic generating device 41 and the second magnetic generating device 42 may include any device that can controllably generate a magnetic field, such as a coil or an electromagnet.

[0076] For example, in some embodiments, the control method further includes adjusting the magnitude of the alternating voltage to adjust the intensity of the electromagnetic radiation. For example, increasing the magnitude of the alternating voltage can increase the intensity of the electromagnetic radiation, thereby adjusting the intensity of the electromagnetic radiation by adjusting the magnitude of the alternating voltage applied to the electrode structure 30.

[0077] In summary, the embodiments of this disclosure provide a micro-antenna based on strong coupling of a magnon-phonon frequency comb and its control method. Through excitation by the electrode structure, multiple acoustic resonant modes are generated in the magnetoelectric heterojunction formed by the piezoelectric layer and the magnetic layer, such as multiple overtone acoustic resonant modes dominated by shear strain. By controlling the dispersion of the magnon in the magnetic layer with a magnetic field, the magnon is coherently coupled with multiple high-overtone phonon modes, forming a magnon-phonon hybrid mode frequency comb with magnetic field control. This enables electromagnetic radiation from the precession of the dynamic magnetic moment at a scale of 1 / 100 of the electromagnetic wave wavelength. The antenna can achieve adjustment of various radiation states, such as controlling the radiation frequency and intensity by adjusting the external magnetic field strength, magnetic field direction, and alternating voltage, making it suitable for micro-tunable radiating antennas. When the applied magnetic field strength changes, the magnon mode exhibits different frequency responses and sequentially satisfies coupling conditions with different phonon resonant modes, achieving a wide range of frequency tunability.

[0078] The following points also need to be explained: (1) The accompanying drawings of the embodiments of this disclosure only involve the structures involved in the embodiments of this disclosure. Other structures can be referred to the general design.

[0079] (2) For clarity, the thickness of layers or regions in the drawings used to describe embodiments of the present disclosure is enlarged or reduced, i.e., these drawings are not drawn to actual scale.

[0080] (3) Where there is no conflict, the embodiments of this disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0081] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. The scope of protection of this disclosure shall be determined by the scope of the claims.

Claims

1. An antenna comprising a piezoelectric layer and a magnetic layer stacked together, and further comprising an electrode structure disposed on at least one surface of the piezoelectric layer. in, The electrode structure is configured to receive alternating voltage to excite the piezoelectric layer to generate acoustic resonance, forming multiple acoustic resonance modes in the piezoelectric layer and the magnetic layer. The frequencies of the multiple acoustic resonance modes are discretely distributed in the operating frequency band, forming a phonon frequency comb. The magnetic layer is configured to controllably generate a magnetic resonant mode whose frequency matches that of the target acoustic resonant mode among the plurality of acoustic resonant modes, so that the magnetic resonant mode is coherently coupled with the target acoustic resonant mode, generating an avoidance crossover phenomenon in the frequency-magnetic field spectrum, forming a magnetic resonant-phonon hybrid mode, and realizing electromagnetic radiation.

2. The antenna according to claim 1, wherein, The thickness of the piezoelectric layer is d. e ,but: ， Among them, C D The piezoelectric stress constant of the piezoelectric layer is... ρ e f0 is the piezoelectric material density of the piezoelectric layer, f0 is the center frequency, the operating frequency band is f1~f2, and f0 = (f1 + f2) / 2.

3. The antenna according to claim 2, wherein, The thickness of the magnetic layer is d. m ,but: ， Among them, C H The constant magnetic field stiffness coefficient of the magnetic layer is given. ρ m The magnetic material density of the magnetic layer is given, Δf is the frequency interval of the phonon frequency comb, and within the operating frequency band, the number of the plurality of acoustic resonant modes is N, where f1-f2=N. Δf, where N is a positive integer greater than or equal to 2.

4. The antenna according to any one of claims 1-3, wherein, The thickness of the magnetic layer is greater than the thickness of the piezoelectric layer.

5. The antenna according to any one of claims 1-3, wherein, The magnetic layer is configured as follows: Under the control of the first magnetic field, a first magnetic resonant mode is generated that matches the first frequency of the first target acoustic resonant mode among the plurality of acoustic resonant modes, so that the first magnetic resonant mode is coupled with the first target acoustic resonant mode to form a first magnetic resonant-phonon hybrid mode, thereby realizing the first electromagnetic radiation state; as well as Under the control of the second magnetic field, a second magnetic resonant mode is generated that matches the second frequency of the second target acoustic resonant mode among the plurality of acoustic resonant modes, so that the second magnetic resonant mode is coupled with the second target acoustic resonant mode to form a second magnetic resonant-phonon hybrid mode, thereby realizing the second electromagnetic radiation state.

6. The antenna according to any one of claims 1-3, wherein, The surface of the piezoelectric layer furthest from the magnetic layer is the first surface, and the surface closest to the magnetic layer is the second surface. The electrode structure includes a first electrode and a second electrode. The first electrode and the second electrode are disposed at a distance from each other on the first surface, and the second surface is in direct contact with the magnetic layer, or The first electrode is disposed on the first surface, the second electrode is disposed in a first region of the second surface, the second electrode is in direct contact with the magnetic layer, and a second region of the second surface other than the first region is in direct contact with the magnetic layer.

7. An electronic device comprising the antenna according to any one of claims 1-6.

8. A method for controlling an antenna, wherein, The antenna includes a piezoelectric layer and a magnetic layer stacked together, and also includes an electrode structure disposed on at least one surface of the piezoelectric layer. The control method includes: An alternating voltage is applied to the electrode structure to excite the piezoelectric layer to generate acoustic resonance, forming multiple acoustic resonance modes in the piezoelectric layer and the magnetic layer. The frequencies of the multiple acoustic resonance modes are discretely distributed in the operating frequency band, forming a phonon frequency comb; and A magnetic field is applied to the magnetic layer to generate a magnetic resonant mode whose frequency matches that of the target acoustic resonant mode among the plurality of acoustic resonant modes. This causes the magnetic resonant mode to coherently couple with the target acoustic resonant mode, resulting in an avoidance crossover phenomenon in the frequency-magnetic field spectrum, forming a magnetic resonant-phonon hybrid mode, and realizing electromagnetic radiation.

9. The antenna according to claim 8, wherein, Applying a magnetic field to the magnetic layer to generate a magnetoresistive sub-mode whose frequency matches that of a target acoustic resonant mode among the plurality of acoustic resonant modes includes: A magnetic field with a first magnetic field strength is applied to the magnetic layer to generate a first magnon mode that matches the first frequency of a first target acoustic resonant mode among the plurality of acoustic resonant modes. This first magnon mode couples with the first target acoustic resonant mode to form a first magnon-phonon hybrid mode, achieving a first electromagnetic radiation state. A magnetic field with a second magnetic field strength is applied to the magnetic layer to generate a second magnetic resonant mode that matches the second frequency of the second target acoustic resonant mode among the plurality of acoustic resonant modes. The second magnetic resonant mode is then coupled with the second target acoustic resonant mode to form a second magnetic resonant-phonon hybrid mode, thereby realizing a second electromagnetic radiation state.

10. The antenna according to claim 8 or 9, wherein, Applying a magnetic field to the magnetic layer includes: The antenna is positioned between a first magnetic generating device and a second magnetic generating device that are positioned opposite each other along an axis, and the angle between the surface of the antenna and the axis is 40 degrees to 50 degrees.

11. The antenna according to claim 8 or 9, wherein, The control method also includes: The intensity of the electromagnetic radiation is adjusted by adjusting the magnitude of the alternating voltage.

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