Magneto-optical device, magneto-optical control system and method

Abstract

The present application provides a magneto-optical device, a magneto-optical control system and a method. The magneto-optical device includes a magneto-optical film, an insulating substrate and a heavy metal film array. The material of the magneto-optical film includes a transition metal oxide containing bismuth, and the magneto-optical film has the characteristic of easy out-of-plane magnetization at room temperature. A heavy metal film array is formed on the surface of the magneto-optical film, which is convenient for using the spin-orbit torque effect of the heavy metal array to achieve the reversal of the out-of-plane magnetization direction of the magneto-optical film, and the magnetization direction in the magnetic insulator film can be reversed without an external magnetic field, so that the magneto-optical device has high stability. The magneto-optical device of the present application can take into account the existing semiconductor micro-nano processing technology, and can make the magneto-optical device have miniaturization and integration characteristics. The magneto-optical device, magneto-optical control system and method in the present application can also be used in the fields of optical storage, optical communication and optical manipulation.

Description

Technical Field

[0001] The present application relates to the technical field of magneto-optical devices, and in particular to a magneto-optical device, a magneto-optical control system and a method. Background Art

[0002] With the development of magneto-optical materials, magneto-optical materials are widely used in information functional devices, involving defense, civil infrastructure, commercial optical communications and other fields. By utilizing the characteristics of magneto-optical materials, magneto-optical switches, magneto-optical storage, magneto-optical isolators, magneto-optical modulators and other magneto-optical devices with various functions can be prepared. It is of great significance to control the magneto-optical response of magneto-optical devices by electrical control.

[0003] In traditional technology, an external magnetic field is generated by passing current through a conductive coil, and then the magnetization direction of the magneto-optical device is controlled by the direction of the generated external magnetic field, thereby achieving the control of the polarization state of the incident light in the magneto-optical device. Due to the divergence and non-locality of the external magnetic field, this method cannot be used to further reduce the size of the magneto-optical device in an integrated device. At the same time, the divergence of the external magnetic field will cause crosstalk with the signal, and some key indicators of the magneto-optical device, such as the magneto-optical response speed under the action of the external magnetic field, will be limited. In addition, since the use of an energized coil to generate a magnetic field will also cause the magneto-optical device to generate Joule heat, this method will greatly reduce the efficiency and power consumption of the magneto-optical device. Summary of the invention

[0004] Based on this, it is necessary to provide a magneto-optical device, a magneto-optical control system and a method to address the problem that magneto-optical devices in the prior art cannot be integrated.

[0005] A magneto-optical device, comprising:

[0006] A magneto-optical film, wherein the material of the magneto-optical film comprises a transition metal oxide containing bismuth;

[0007] an insulating substrate, on which the magneto-optical film is epitaxially grown;

[0008] A heavy metal film array is formed on the surface of the magneto-optical film, and the heavy metal film array is used to change the out-of-plane magnetization direction of the magneto-optical film based on currents applied in different directions.

[0009] In one embodiment, the transition metal oxide comprises a 3d transition metal oxide.

[0010] In one embodiment, the thickness of the magneto-optical film is less than 100 nanometers.

[0011] In one embodiment, the magneto-optical film is epitaxially grown on the insulating substrate by a laser pulse deposition method.

[0012] In one embodiment, the magneto-optical film is epitaxially grown on the insulating substrate by a liquid phase epitaxy method.

[0013] In one embodiment, the metal elements in the heavy metal film array include platinum, tantalum and bismuth.

[0014] A magneto-optical control system, characterized in that the magneto-optical control system comprises the magneto-optical device according to claims 1 to 6, a power supply and metal leads, wherein:

[0015] The power supply is used to provide current;

[0016] The metal leads are respectively connected to the heavy metal film array and the power source, and are used to introduce current into the heavy metal array.

[0017] In one embodiment, the magneto-optical control system further comprises:

[0018] External polarized light;

[0019] The detection device is used to detect the rotation angle of the polarization plane of the external polarized light after the external polarized light is transmitted through the magneto-optical film.

[0020] A magneto-optical control method, which is applied to the above magneto-optical control system, comprises:

[0021] Controlling the transmission of external polarized light through magneto-optical film;

[0022] Using a power source to provide currents in different directions to the heavy metal film array through metal leads, and using the spin-orbit torque effect of the heavy metal film array to change the out-of-plane magnetization direction of the magneto-optical film;

[0023] A detection device is used to detect the rotation angle change of the polarization plane of the external polarized light transmitted through the magneto-optical film, and the detection result of the detection device is used to reflect the working state of the magneto-optical device.

[0024] In one embodiment, the method of changing the out-of-plane magnetization direction of the magneto-optical film by utilizing the spin-orbit torque effect of the heavy metal film array comprises:

[0025] When the currents of different directions pass through the heavy metal film array, effective fields of different directions are formed inside the heavy metal film array. The effective fields drive the spin orientation in the magneto-optical film to flip, thereby flipping the magnetization direction out of the magneto-optical film.

[0026] The present application provides a magneto-optical device, a magneto-optical control system and a method. The magneto-optical film material of the magneto-optical device is a transition oxide containing bismuth elements. This type of magneto-optical material has a high magneto-optical coefficient at room temperature and above room temperature, and has a spontaneous out-of-plane easy magnetization characteristic. The magneto-optical film includes bismuth elements to ensure that there is a strong spin-orbit coupling effect in the magneto-optical film. The magneto-optical film includes a transition oxide, and the transition oxide is used to provide magnetism for the magneto-optical film to ensure that the magneto-optical film has an out-of-plane spontaneous magnetization characteristic. A heavy metal film array is formed on the surface of the magneto-optical film. The heavy metal film array is used to use the spin-orbit torque effect to change the out-of-plane magnetization direction of the magneto-optical film based on the current applied in different directions. The out-of-plane magnetization direction in the magneto-optical film can be changed without an external magnetic field, so that the magneto-optical device has high stability. The magneto-optical device described in the embodiment of the present application can take into account the existing semiconductor micro-nano processing technology, and can make the magneto-optical device have miniaturization and integration characteristics.

[0027] In the magneto-optical control system provided by the present application, the power supply provides currents of different directions to the heavy metal film array through metal leads, and the heavy metal film array uses the spin-orbit torque effect to flip the out-of-plane magnetization direction of the magneto-optical film. The magneto-optical control method provided by the present application includes: controlling the external polarized light to transmit through the magneto-optical film; using the power supply to provide currents of different directions to the heavy metal film array through metal leads, and using the spin-orbit torque effect of the heavy metal film array to change the out-of-plane magnetization direction of the magneto-optical film; using a detection device to detect the rotation angle change of the polarization plane of the external polarized light transmitted through the magneto-optical film, and using the detection result of the detection device to reflect the working state of the magneto-optical device. Therefore, the magneto-optical device, magneto-optical control system and method provided by the present application can realize the flipping of the out-of-plane magnetization direction of the magneto-optical film without the need for an external magnetic field, and then realize the regulation of the magneto-optical response of the magneto-optical device by electric control under working conditions at room temperature and above room temperature, which has the advantage of integration and can be widely used in optical storage, optical communication and optical manipulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a structural diagram of a magneto-optical device in one embodiment;

[0029] Figure 2 The structure of a magneto-optical control system in one embodiment is shown in FIG. Figure 1 ;

[0030] Figure 3 A magneto-optical control system in one embodiment Figure 1 ;

[0031] Figure 4 A magneto-optical control system in one embodiment Figure 2 ;

[0032] Figure 5 The structure of the magneto-optical control system in another embodiment is shown in FIG. Figure 2 ;

[0033] Figure 6 The structure of the magneto-optical control system in another embodiment is shown in FIG. Figure 3 ;

[0034] Figure 7 The structure of the magneto-optical control system in another embodiment is shown in FIG. Figure 4 .

[0035] Figure Number:

[0036] Magneto-optical film 100;

[0037] Figure Number:

[0038] Magneto-optical device 10; magneto-optical film 100; insulating substrate 200; heavy metal film array 300; power supply 400; metal lead 500; external polarized light 600; detection device 700; optical fiber 800; bottom electrode 900. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0040] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of this application, it should be understood that the orientation or position relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to this application.

[0041] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0042] Magneto-optical materials are a type of material widely used in information functional devices. The application of magneto-optical materials involves defense, civil infrastructure, commercial optical communications and other fields. Magneto-optical materials generally refer to materials with spontaneous magnetization. Under the action of an external magnetic field, magneto-optical materials cause the polarization plane of incident or reflected linearly polarized light or circularly polarized light to deflect at a certain angle. The principles mainly include the Faraday effect, the Kerr effect and the Cotton-Morton effect. In the prior art, various optical functional devices such as magneto-optical switches, magneto-optical storage, magneto-optical isolators, and magneto-optical modulators can be prepared by utilizing the above characteristics of magneto-optical materials.

[0043] At present, there is no ideal technology that can be widely used in integrated micro-nano devices to control the magneto-optical response state of magneto-optical devices by means of electrical control under working conditions at room temperature or above. This is mainly limited by two reasons. The first reason is that magneto-optical materials need to have the main characteristics of spontaneous magnetization at room temperature or above, high magneto-optical coefficient and insulation. An important prerequisite for realizing the magneto-optical performance of electrically controlled magneto-optical devices is that the magneto-optical devices to be used need to take into account the above-mentioned characteristics at the same time; the second reason is that it is necessary to meet the requirements of controlling the magneto-optical response state of magneto-optical devices by means of electrical control in micro-nano integrated devices.

[0044] At present, the general method in the prior art is to pass current through the coil, use the conductive coil with current to generate an external magnetic field, and then use the direction of the external magnetic field generated by the conductive coil to control the magnetization direction of the magneto-optical device, so as to realize the regulation of the polarization state of the light transmitted through the magneto-optical device. Since the external magnetic field generated by the energized coil has the characteristics of divergence and non-locality, this method cannot be used in integrated devices, and the size of the magneto-optical device cannot be reduced to a smaller size after using this method. At the same time, the divergence of the external magnetic field generated by the energized coil will cause crosstalk signals. Under the action of the external magnetic field generated by the energized coil, some key indicators such as the magneto-optical response speed of the magneto-optical device will be limited. In addition, the external magnetic field generated by the energized coil will also cause the magneto-optical device to generate a certain amount of Joule heat, which will also reduce the efficiency and power consumption of the magneto-optical device.

[0045] For consideration of this type of question, see Figure 1 , an embodiment of the present application provides a magneto-optical device 10. The magneto-optical device 10 includes a magneto-optical film 100, an insulating substrate 200, and a heavy metal film array 300. The material of the magneto-optical film 100 includes a transition metal oxide containing bismuth. The magneto-optical film 100 is epitaxially grown on the insulating substrate 200. A heavy metal film array 300 is formed on the surface of the magneto-optical film 100. The heavy metal film array 300 changes the out-of-plane magnetization direction of the magneto-optical film 100 based on the currents applied in different directions.

[0046] In the embodiment of the present application, the oxide magnetic transition oxide containing bismuth element is used as magneto-optical material in the magneto-optical device 10. In the near-infrared light band, the material of the magneto-optical film 100 containing bismuth element has a higher specific Faraday rotation angle. When the magneto-optical film 100 is magnetized out of the plane, the polarization plane of the external linear polarized light 600 transmitted through the magneto-optical film 100 can rotate in different directions. The heavy metal film array 300 formed on the magneto-optical film 100 in the embodiment of the present application can change the magnetization direction of the magneto-optical film 100 out of the plane based on the different directions of the current passing through the heavy metal film array 300, and then the polarization state of the external linear polarized light 600 transmitted through the magneto-optical film 100 can be changed, thereby realizing the working state of the magneto-optical device 10 controlled by the current.

[0047] The material of the magneto-optical film 100 in the embodiment of the present application is a transition oxide containing bismuth. Such magneto-optical materials have a high magneto-optical coefficient at room temperature and above, and have spontaneous out-of-plane easy magnetization characteristics. The magneto-optical film 100 in the embodiment of the present application includes bismuth elements, thereby ensuring that there is a strong spin-orbit coupling effect in the magneto-optical film 100. The magneto-optical film 100 in the embodiment of the present application includes a transition oxide, which is used to provide magnetism for the magneto-optical film 100 and ensure that the magneto-optical film 100 has out-of-plane spontaneous magnetization characteristics. In addition, the magneto-optical film 100 has insulating properties, and the magneto-optical film 100 is an insulator film.

[0048] In the embodiment of the present application, a highly insulating magneto-optical film 100 is epitaxially grown on an insulating substrate 200. The magneto-optical film 100 is transparent in the visible light range, and the external polarized light 600 can directly transmit through the magneto-optical film 100 and its insulating substrate 200.

[0049] The spin orbit torque (SOT) effect in spin electronics is a spin control method. In ferromagnetic films, the spin orbit torque (SOT) effect can be used to achieve the up and down flipping of the out-of-plane magnetization direction in some ferromagnetic films that are easily magnetized out of the plane, and this method has good non-volatility. In order to use the spin orbit torque (SOT) effect to achieve the flipping of the out-of-plane magnetization direction in the magneto-optical film 100, the surface of the magneto-optical film 100 can be processed to form a heavy metal film array 300. A heavy metal film array 300 is formed on the surface of the magneto-optical film 100, and the heavy metal film array 300 is used to use the spin orbit torque (SOT) effect to change the out-of-plane magnetization direction of the magneto-optical film 100 based on the current applied in different directions. When the heavy metal film array 300 passes through the current of different directions, due to the effective fields of different directions formed inside the heavy metal film array 300, the in-plane spin orientation in the magneto-optical film 100 can be driven to flip, and then the out-of-plane magnetization direction of the magneto-optical film 100 can be driven to flip, thereby realizing the flipping of the magnetization direction driven by current, realizing the magneto-optical response of the electrically controlled magneto-optical device 10 under room temperature conditions, and the size of the above-mentioned magneto-optical device 10 can be greatly reduced without setting an external magnetic field. At the same time, due to the different out-of-plane magnetization directions generated by the magneto-optical film 100 under the action of currents of different directions, the polarization plane of the polarized light transmitted through the magneto-optical film 100 can rotate in different directions under the action of magnetic fields of different out-of-plane magnetization directions, and the different working states of the magneto-optical device 10 can be directly recorded by reading the rotation angle of the polarization plane of the polarized light.

[0050] In the embodiment of the present application, the heavy metal film array 300 can be formed on the surface of the magneto-optical film 100 by using the photolithography technology in the micro-nano processing technology, and the magneto-optical film 100 is processed by the existing photolithography technology to form the heavy metal film array 300 on the magneto-optical film 100. The micro-nano processing technology of the magneto-optical film 100 in the embodiment of the present application has good compatibility with the current semiconductor processing technology, so that the magneto-optical device 10 in the embodiment of the present application and the current integration process have good matching, and the size of the magneto-optical device 10 can be greatly reduced. Therefore, the magneto-optical device 10 provided in the embodiment of the present application has the characteristics of miniaturization and integration.

[0051] In summary, the magneto-optical device 10 provided in the embodiment of the present application can meet the requirements of regulating the magneto-optical response of the magneto-optical device 10 by means of electrical control under working conditions at room temperature or above room temperature. The embodiment of the present application can achieve the reversal of the out-of-plane magnetization direction in the magneto-optical film 100 without the need for an external magnetic field, so that the magneto-optical device 10 has high stability. The magneto-optical device 10 described in the embodiment of the present application can take into account the existing semiconductor micro-nano processing technology, so that the magneto-optical device 10 has the characteristics of miniaturization and integration. The magneto-optical device 10 provided in the embodiment of the present application can also be used in the fields of optical storage, optical communication, and optical manipulation.

[0052] In one embodiment, the transition metal oxide comprises a 3d transition metal oxide.

[0053] The material of the magneto-optical film 100 in the embodiment of the present application includes a transition metal oxide containing bismuth. The bismuth element ensures that there is a strong spin-orbit coupling effect in the magneto-optical film 100 to improve the magneto-optical response of the magneto-optical film 100. The transition metal oxide includes a 3d transition metal oxide, which is used to provide magnetism for the magneto-optical film 100, ensuring that the material of the magneto-optical film 100 has a high magneto-optical coefficient, and at the same time has a spontaneous out-of-plane easy magnetization characteristic, and also ensures that the magneto-optical film 100 is a magnetic insulator.

[0054] In one embodiment, the thickness of the magneto-optical film 100 is less than 100 nanometers.

[0055] The heavy metal film array 300 in the embodiment of the present application is used to change the out-of-plane magnetization direction of the magneto-optical film 100 based on the currents applied in different directions by using the spin-orbit torque (SOT) effect. The magneto-optical film 100 needs to meet certain thickness requirements to change the out-of-plane magnetization direction of the magneto-optical film 100 by using the spin-orbit torque (SOT) effect. The thickness of the magneto-optical film 100 in the embodiment of the present application is less than 100 nanometers, ensuring that when currents in different directions pass through the heavy metal film array 300 formed by the magneto-optical film 100, the effective field formed inside the heavy metal film array 300 can drive the flipping of the in-plane spin orientation in the magneto-optical film 100, and then drive the flipping of the out-of-plane magnetization direction of the magneto-optical film 100, so as to change the out-of-plane magnetization direction of the magneto-optical film 100 by current.

[0056] In one embodiment, the magneto-optical film 100 is epitaxially grown on the insulating substrate 200 by a laser pulse deposition method.

[0057] In the embodiment of the present application, the magneto-optical film 100 in the magneto-optical device 10 can be epitaxially grown on the insulating substrate 200 by a laser pulse deposition method. The epitaxial growth direction of the magneto-optical film 100 has a certain relationship with the internal crystal structure and direction of the insulating substrate 200, and the epitaxial growth direction of the magneto-optical film 100 includes in-plane epitaxial growth and out-of-plane epitaxial growth. The laser pulse deposition method has a high deposition rate, a short entire test cycle, low substrate temperature requirements, and can prepare a uniform film. Therefore, the laser pulse deposition method can be used to prepare the magneto-optical film 100.

[0058] In one embodiment, the magneto-optical film 100 is epitaxially grown on the insulating substrate 200 by a liquid phase epitaxy method.

[0059] In the embodiment of the present application, the magneto-optical film 100 in the magneto-optical device 10 can be epitaxially grown on the insulating substrate 200 by the liquid phase epitaxy method. The epitaxial growth direction of the magneto-optical film 100 has a certain relationship with the internal crystal structure and direction of the insulating substrate 200, and the epitaxial growth direction of the magneto-optical film 100 includes in-plane epitaxial growth and out-of-plane epitaxial growth. In the liquid phase epitaxy method, the growth equipment is relatively simple, the growth rate is relatively high, there are no highly toxic and highly corrosive raw materials and products in the growth system, and the operation is safe and simple. Therefore, the magneto-optical film 100 can be epitaxially grown on the insulating substrate 200 by the liquid phase epitaxy method.

[0060] In one embodiment, the metal elements in the heavy metal film array 300 include platinum, tantalum and bismuth.

[0061] In the embodiment of the present application, the heavy metal film array 300 is used to utilize the spin-orbit torque effect to change the out-of-plane magnetization direction of the magneto-optical film 100 based on the currents applied in different directions. The metal elements contained in the heavy metal film array 300 include but are not limited to heavy metals such as platinum, tantalum and bismuth.

[0062] The present application embodiment provides a magneto-optical control system including the magneto-optical device 10 described above, and the magneto-optical control system also includes a power supply 400 and a metal lead 500. The power supply 400 is used to provide current. The metal lead 500 is respectively connected to the heavy metal film array 300 and the power supply 400, and is used to introduce current to the heavy metal film array 300.

[0063] Please also see Figure 2The magneto-optical control system provided in the embodiment of the present application includes a magneto-optical film 100, an insulating substrate 200, a heavy metal film array 300, a power supply 400 and a metal lead 500. In the magneto-optical control system in the embodiment of the present application, the power supply 400 provides currents of different directions to the heavy metal film array 300 through the metal lead 500, and the heavy metal film array 300 uses the spin-orbit torque effect to flip the out-of-plane magnetization direction of the magneto-optical film 100. In the embodiment of the present application, the magneto-optical control system does not need to use the external magnetic field generated by the conductive coil to control the magnetization direction of the magneto-optical device 10, but directly controls the out-of-plane magnetization direction of the magnetic device by applying currents of different directions to the heavy metal film array 300, so that the magneto-optical control system has high stability. The magneto-optical film 100 is a magnetic insulator film, which has a high Faraday rotation angle in the near-infrared band. When the magneto-optical film 100 spontaneously flips its magnetization direction, the polarization plane of the polarized light transmitted through the magneto-optical film 100 can be rotated in different directions, thereby realizing the working state of the current-controlled magneto-optical device.

[0064] In the embodiment of the present application, the heavy metal film array 300 is formed on the magneto-optical film 100 by photolithography in the micro-nano processing technology, so that the magneto-optical control system has the characteristics of integration. The use of semiconductor micro-nano processing technology to process the magneto-optical control system can greatly reduce the size of the magneto-optical control system, making it miniaturized, and can increase the application range of the magneto-optical control system.

[0065] In one embodiment, the magneto-optical control system further comprises an external polarized light 600 and a detection device 700. The detection device 700 is used to detect the rotation angle of the polarization plane of the external polarized light 600 after the external polarized light 600 transmits through the magneto-optical film 100.

[0066] In the embodiment of the present application, the external polarized light 600 includes but is not limited to linear polarized light and circular polarized light. In the magneto-optical control system, the external polarized light 600 is transmitted through the magneto-optical film 100 and then received by the detection device 700. The detection device 700 can detect the rotation angle of the polarization plane of the external polarized light 600 after it is transmitted through the magneto-optical film 100. The regulation of the working state of the magneto-optical device 10 by the current can be obtained through the detection result of the detection device 700. The detection accuracy of the detection device 700 for the external polarized light 600 can reach 0.01urad. The higher the detection accuracy of the detection device 700, the more accurately the regulation of the working state of the magneto-optical device 10 by the current can be obtained.

[0067] In the drawings of this application, E may represent the polarization direction of polarized light. Figure 3-Figure 4 ,exist Figure 3 and Figure 4The middle power source 400 provides currents of different directions to the heavy metal film array 300 through the metal lead 500. The heavy metal film array 300 utilizes the spin-orbit torque effect to flip the out-of-plane magnetization direction of the magneto-optical film 100, so that the polarization direction of the external polarized light 600 transmitted through the magneto-optical film 100 changes.

[0068] Please also see Figure 5 In one embodiment, the magneto-optical control system may further include an optical fiber 800. The external polarized light 600 is transmitted through the magneto-optical film 100 through the optical fiber 800. The magneto-optical control system can control the flipping of the out-of-plane magnetization direction of the magneto-optical film 100 by applying currents of different directions to the heavy metal film array 300, and utilize the spin-orbit torque (SOT) effect, thereby controlling the change of the polarization plane rotation angle of the external polarized light 600 transmitted through the magneto-optical film 100. The above-mentioned magneto-optical control system can also be used as a magneto-optical switch, which can realize the passing and cutting off of specific polarized light. In the embodiment of the present application, the number of optical fibers 800 includes but is not limited to one, and multiple optical fibers 800 can be set according to requirements. Each optical fiber 800 corresponds to an external polarized light 600 and a power supply 400.

[0069] The direction in which the external polarized light 600 is transmitted through the magneto-optical film 100 is consistent with the direction of the epitaxial growth of the magneto-optical film 100. The epitaxial growth direction of the magneto-optical film 100 includes in-plane epitaxial growth and out-of-plane epitaxial growth. When the magneto-optical film 100 is epitaxially grown on the insulating substrate 200 along the in-plane, the external polarized light 600 is transmitted through the magneto-optical film 100 along the in-plane direction. When the magneto-optical film 100 is epitaxially grown on the insulating substrate 200 along the out-of-plane direction, the external polarized light 600 is transmitted through the magneto-optical film 100 along the out-of-plane direction. Please refer to Figure 1-Figure 7 ,exist Figure 1-Figure 5 and Figure 7 In the embodiment, the magneto-optical film 100 is epitaxially grown on the insulating substrate 200 in an out-of-plane direction. At this time, the external polarized light 600 is transmitted through the magneto-optical film 100 in an out-of-plane direction. Figure 6 In the embodiment, the magneto-optical film 100 is epitaxially grown on the surface of the insulating substrate 200 along the plane, and the external polarized light 600 is transmitted through the magneto-optical film 100 along the in-plane direction. Therefore, controlling the epitaxial growth direction of the magneto-optical film 100 can realize the light transmission in the in-plane direction, and by controlling the current input in different directions to the heavy metal film array 300, the modulation and isolation of the specific external polarized light 600 can be realized, so that the electro-optical modulation in the photonic chip can be realized.

[0070] Please also see Figure 7In one embodiment, the magneto-optical control system further includes a bottom electrode 900. The bottom electrode 900 is located between the magneto-optical film 100 and the insulating substrate 200, and currents of different directions can be applied to the heavy metal film array 300 and the bottom electrode 900 through the power supply 400. There is a strong spin-orbit coupling effect in the magneto-optical film 100 located between the bottom electrode 900 and the heavy metal film array 300. Under the action of currents of different directions between the heavy metal film array 300 and the bottom electrode 900, the magneto-optical film 100 can achieve the reversal of the magnetization direction outside the plane of the magneto-optical film 100. When the magnetization direction outside the plane of the magneto-optical film 100 is reversed, the polarization plane of the external polarized light 600 transmitted through the magneto-optical film 100 can be rotated in different directions, thereby achieving the working state of the current-controlled magneto-optical device 10.

[0071] An embodiment of the present application provides a magneto-optical control method, which is applied to the above-mentioned magneto-optical control system.

[0072] Magneto-optical control methods include:

[0073] Controlling the external polarized light 600 to transmit through the magneto-optical film 100;

[0074] The power source 400 is used to provide currents of different directions to the heavy metal film array 300 through the metal lead 500, and the spin-orbit torque effect of the heavy metal film array 300 is used to change the out-of-plane magnetization direction of the magneto-optical film 100;

[0075] The detection device 700 is used to detect the rotation angle change of the polarization plane of the external polarized light 600 that transmits the magneto-optical film 100, and the detection result of the detection device 700 is used to reflect the working state of the magneto-optical device 10.

[0076] The magneto-optical control method in the embodiment of the present application controls the external polarized light 600 to be transmitted through the magneto-optical film 100 along the direction of the epitaxial growth of the magneto-optical film 100 according to the epitaxial growth direction of the magneto-optical film 100. The power supply 400 provides currents of different directions to the heavy metal film array 300 through the metal lead 500. When currents of different directions pass through the heavy metal film array 300, the spin-orbit torque effect in the heavy metal film array 300 is used to achieve the reversal of the magnetization direction of the magneto-optical film 100, so that the reversal of the magnetization direction in the magneto-optical film 100 can be achieved without the need for an external magnetic field, and has high stability. In addition, since the magneto-optical film 100 has a high Faraday rotation angle in the near-infrared band, when the magneto-optical film 100 spontaneously reverses its magnetization direction, the polarization plane of the external polarized light 600 transmitted through the magneto-optical film 100 can be rotated in different directions, thereby achieving the working state of the current-controlled magneto-optical device 10.

[0077] In one embodiment, using the spin-orbit torque effect of the heavy metal film array 300 to change the out-of-plane magnetization direction of the magneto-optical film 100 includes:

[0078] When currents of different directions pass through the heavy metal film array 300, effective fields of different directions are formed inside the heavy metal film array 300. The effective fields drive the spin orientation of the magneto-optical film 100 to flip, thereby flipping the magnetization direction of the magneto-optical film 100 out of the plane.

[0079] In order to realize the reversal of the magnetization direction in the magneto-optical film 100 by utilizing the SOT effect, it is necessary to process the heavy metal film array 300 on the surface of the magneto-optical film 100 by utilizing the photolithography technology in the micro-nano processing technology. This process has good compatibility with the current semiconductor processing technology, which also makes this type of magneto-optical device 10 have good matching with the current integration process. When the heavy metal film array 300 passes through the current of different directions, due to the different orientation effective fields formed inside the heavy metal film array 300, the reversal of the spin orientation in the plane of the magneto-optical film 100 can be driven, and then the magnetization direction outside the magneto-optical film 100 can be driven to be reversed, thereby realizing the reversal of the magnetization direction of the magneto-optical film 100 driven by current. At the same time, due to the effect of the different magnetization directions of the magneto-optical film 100, the external polarized light 600 transmitted through the magneto-optical film 100 will be deflected in different directions of the polarization plane, and different signals can be directly recorded by reading the deflection angle of the polarization plane. Based on this type of magneto-optical control system and method, we can also apply the magneto-optical device 10 in specific functional devices to achieve the regulation of the polarization state of light.

[0080] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0081] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A magneto-optical device, It is characterized in that The magneto-optical device comprises: A magneto-optical film (100), wherein the material of the magneto-optical film (100) comprises a transition metal oxide containing a bismuth element; An insulating substrate (200), on which the magneto-optical film (100) is epitaxially grown; A heavy metal film array (300) is formed on the surface of the magneto-optical film (100), and the heavy metal film array (300) is used to utilize the spin-orbit torque effect to change the out-of-plane magnetization direction of the magneto-optical film (100) based on currents of different directions directly applied to the heavy metal film array (300), wherein metal leads (500) are respectively connected to the heavy metal film array (300) and a power source (400) for introducing current into the heavy metal film array (300).

2. The magneto-optical device according to claim 1, It is characterized in that The transition metal oxides include 3d transition metal oxides.

3. The magneto-optical device according to claim 1, It is characterized in that The thickness of the magneto-optical film (100) is less than 100 nanometers.

4. The magneto-optical device according to claim 1, It is characterized in that The magneto-optical film (100) is epitaxially grown on the insulating substrate (200) by a laser pulse deposition method.

5. The magneto-optical device according to claim 1, It is characterized in that The magneto-optical film (100) is epitaxially grown on the insulating substrate (200) by a liquid phase epitaxy method.

6. The magneto-optical device according to claim 1, It is characterized in that The metal elements in the heavy metal thin film array (300) include platinum, tantalum and bismuth.

7. A magneto-optical control system, It is characterized in that The magneto-optical control system comprises the magneto-optical device according to any one of claims 1 to 6, as well as a power supply (400) and a metal lead (500), wherein: The power supply (400) is used to provide current; The metal lead wires (500) are respectively connected to the heavy metal thin film array (300) and the power source (400), and are used to introduce current into the heavy metal thin film array.

8. The magneto-optical control system according to claim 7, It is characterized in that The magneto-optical control system further comprises: External polarized light (600); The detection device (700) is used to detect the rotation angle of the polarization plane of the external polarized light (600) after the external polarized light (600) is transmitted through the magneto-optical film (100).

9. A magneto-optical control method, It is characterized in that The magneto-optical control method is applied to the magneto-optical control system according to claim 8, and the method comprises: Controlling the external polarized light (600) to transmit through the magneto-optical film (100); Using a power source (400) to provide currents of different directions to the heavy metal film array (300) through a metal lead (500), and using the spin-orbit torque effect of the heavy metal film array (300) to change the out-of-plane magnetization direction of the magneto-optical film (100); Using a detection device (700) to detect the change in the rotation angle of the polarization plane of the external polarized light (600) transmitted through the magneto-optical film (100); The detection result of the detection device (700) is used to reflect the working state of the magneto-optical device.

10. The magneto-optical control method according to claim 9, It is characterized in that The method of changing the out-of-plane magnetization direction of the magneto-optical film (100) by utilizing the spin-orbit torque effect of the heavy metal film array (300) comprises: When currents of different directions pass through the heavy metal film array (300), effective fields of different directions are formed inside the heavy metal film array (300), and the effective fields drive the in-plane spin orientation of the magneto-optical film (100) to flip, thereby causing the out-of-plane magnetization direction of the magneto-optical film (100) to flip.

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