Two-dimensional ferroelectric photovoltaic polarimeter and manufacturing method thereof, and polarized light detection method

Abstract

The present application relates to a two-dimensional ferroelectric photovoltaic polarimeter, a manufacturing method thereof, and a polarized light detection method. The two-dimensional ferroelectric photovoltaic polarimeter comprises: a substrate; a support layer disposed on the substrate, the support layer forming steps with the substrate on both sides along the width direction; a ferroelectric layer comprising a first electrode region, a first strain gradient region, a connection region, a second strain gradient region, and a second electrode region sequentially connected along the width direction, the connection region being stacked on the support layer, the first electrode region and the second electrode region being disposed on the substrate, the ferroelectric layer being a two-dimensional material such that both the first strain gradient region and the second strain gradient region are used to achieve a bulk photovoltaic effect; an electrode pattern comprising a first electrode electrically connected to the first electrode region and a second electrode electrically connected to the second electrode region; a first light transmission portion for transmitting light to the first strain gradient region; and a second light transmission portion for transmitting light to the second strain gradient region. The two-dimensional ferroelectric photovoltaic polarimeter can be used for polarized light detection.

Description

Technical Field

[0001] The present application relates to the technical field of photoelectric detectors, and in particular to a two-dimensional ferroelectric photovoltaic polarimeter and a manufacturing method thereof, and a polarized light detection method. Background Art

[0002] Photoelectric detection devices are able to convert light signals into electrical signals. Photoelectric detection devices are widely used in radar guidance, spectral analysis, photographic imaging, and optical communications. In recent years, with the rapid development of fields such as artificial intelligence and the Internet of Things, higher requirements have been placed on the low energy consumption and multi-function of photoelectric detection devices. The inherent properties of the light field, such as polarization, intensity, and wavelength, provide multi-dimensional optical information for many applications, including but not limited to environmental monitoring, thermal imaging, medical diagnosis, and free-space communication. The simultaneous detection of this multi-dimensional optical information provides multiple degrees of freedom for accurately identifying different targets in complex environments and performing multiple forms of tasks in parallel. However, identifying light information is relatively difficult.

[0003] To determine the polarization properties of light, traditional polarimeter systems require a series of optoelectronic components, including lenses, prisms, polarizers, wave plates, filters, photodetectors, and mechanical components, arranged in series along the optical path. These components are bulky and require complex manufacturing steps, making them difficult to miniaturize and integrate. Furthermore, the extensive use of optical components leads to high costs.

[0004] Photovoltaic polarization detectors require two anisotropic semiconductor materials to form a heterojunction, enabling operation without an external electric field. While the anisotropy of semiconductor materials can typically be exploited to detect the angle of linearly polarized light, further advancements in detecting multiple polarization states generally require the design of a complex optical system. While artificial metasurfaces can replace traditional optical systems in some technologies, their essence remains a superposition of a grating module and a photodetector, further complicating the design of photovoltaic polarimeter systems based on artificial metasurfaces.

[0005] In addition, polarization detectors require an additional power meter to decouple the relationship between optical power and polarization angle. Since light with a polarization angle of θ and light with a polarization angle of 180°-θ have the same detection value, the two lights cannot be distinguished. Summary of the Invention

[0006] Based on this, it is necessary to provide a two-dimensional ferroelectric photovoltaic polarimeter and a manufacturing method thereof, as well as a polarized light detection method to address at least one of the above problems.

[0007] In a first aspect, the present application provides a two-dimensional ferroelectric photovoltaic polarimeter, which includes: a substrate; a support layer, arranged on the substrate, the support layer forming steps with the substrate on both sides along the width direction; a ferroelectric layer, including a first electrode region, a first strain gradient region, a connection region, a second strain gradient region and a second electrode region connected in sequence along the width direction, the connection region is stacked on the support layer, the first electrode region and the second electrode region are arranged on the substrate, the material of the ferroelectric layer is a two-dimensional material, so that the first strain gradient region and the second strain gradient region are both used to realize the bulk photovoltaic effect; an electrode pattern, including a first electrode electrically connected to the first electrode region and a second electrode electrically connected to the second electrode region; a first light transmission portion, used to transmit light to the first strain gradient region; and a second light transmission portion, used to transmit light to the second strain gradient region.

[0008] By arranging a support layer in coordination with the substrate, the ferroelectric layer is restricted to a first strain gradient region and a second strain gradient region. At the same time, a first light transmission portion and a second light transmission portion are respectively arranged to correspond one-to-one to the first strain gradient region and the second strain gradient region. Light with the same characteristics can be irradiated to the first strain gradient region and the second strain gradient region respectively, so that the two-dimensional ferroelectric photovoltaic polarimeter can output different currents for light with the same polarization characteristics when used for detection.

[0009] The two-dimensional ferroelectric photovoltaic polarimeter described in this application can be used for polarized light detection, achieving accurate polarization angle measurement. It can also be used to decouple optical power and polarization angle, enabling multifunctional integration. The two-dimensional ferroelectric photovoltaic polarimeter has a simple structure, eliminating the need for additional optical components. It operates without the need for an external electric field power supply and is compact, reaching sizes down to hundreds of microns.

[0010] In some embodiments, the material of the ferroelectric layer includes binary niobium oxyhalide. Exemplarily, the material of the support layer includes at least one of h-BN, silicon nitride, silicon oxide, and aluminum nitride.

[0011] This setup results in a relatively large anisotropy of the binary niobium oxyhalide, minimizing the error in polarization measurements using a two-dimensional ferroelectric photovoltaic polarimeter. The two-dimensional ferroelectric photovoltaic polarimeter can detect light in the wavelength range of 300nm to 450nm. The insulating support layer ensures support and limits the strain gradient in the ferroelectric layer.

[0012] In some embodiments, the material of the ferroelectric layer is NbOBr2 with the b-axis parallel to the width direction.

[0013] With this setup, the performance of the two-dimensional ferroelectric photovoltaic polarimeter is good.

[0014] In some embodiments, the ferroelectric layer has a thickness ranging from 30 nm to 50 nm. Exemplarily, the support layer has a thickness ranging from 80 nm to 200 nm.

[0015] Such arrangement is easy to manufacture and can also ensure better performance.

[0016] Exemplarily, the support layer has a size ranging from 6 μm to 20 μm in the width direction. Exemplarily, the first light transmitting portion is close to the support layer relative to the first electrode, and the second light transmitting portion is close to the support layer relative to the second electrode.

[0017] With such an arrangement, the first strain gradient region and the second strain gradient region can have a higher strain gradient, and light can be irradiated at a location with greater stress.

[0018] In some embodiments, the first light transmitting portion and the second light transmitting portion are optical waveguides disposed on the substrate, respectively, and the two-dimensional ferroelectric photovoltaic polarimeter further includes an upper cladding layer covering the optical waveguides.

[0019] With this setup, the manufacturing process of the two-dimensional ferroelectric photovoltaic polarimeter is compatible with the silicon photonic chip process and is easy to integrate.

[0020] In some embodiments, the two-dimensional ferroelectric photovoltaic polarimeter further includes an input optical path, a current collection circuit, and a processor, wherein the input optical path is coupled to the first optical transmission part and the second optical transmission part, respectively, the current collection circuit is electrically connected to the electrode pattern, and the processor is electrically connected to the current collection circuit, and the processor is configured to: calculate the polarization angle of the polarized light and the optical power based on the response current of the first strain gradient region and the response current of the second strain gradient region.

[0021] With such an arrangement, the two-dimensional ferroelectric photovoltaic polarimeter can transmit the same light to the first strain gradient region and the second strain gradient region respectively; can accurately obtain the polarization angle and the optical power.

[0022] In a second aspect, the present application provides a method for manufacturing a two-dimensional ferroelectric photovoltaic polarimeter, the method comprising: providing a substrate; forming a first light transmission portion and a second light transmission portion; setting a support layer, the support layer forming steps with the substrate on both sides along the width direction; setting a ferroelectric layer on the support layer and the substrate, wherein the ferroelectric layer comprises a first electrode region, a first strain gradient region, a connection region, a second strain gradient region and a second electrode region connected in sequence along the width direction, the connection region is stacked on the support layer, the first electrode region and the second electrode region are arranged on the substrate, the material of the ferroelectric layer is a two-dimensional material, so that the first strain gradient region and the second strain gradient region are both used to realize the bulk photovoltaic effect; the first light transmission portion is used to transmit light to the first strain gradient region, and the second light transmission portion is used to transmit light to the second strain gradient region; and forming an electrode pattern, the electrode pattern comprising a first electrode electrically connected to the first electrode region and a second electrode electrically connected to the second electrode region.

[0023] The manufacturing method of the embodiment of the present application can manufacture a two-dimensional ferroelectric photovoltaic polarimeter.

[0024] In a third aspect, the present application provides a method for detecting polarized light, utilizing the aforementioned two-dimensional ferroelectric photovoltaic polarimeter or the two-dimensional ferroelectric photovoltaic polarimeter obtained by the aforementioned manufacturing method. The detection method comprises: transmitting first polarized light to a first strain gradient region via a first optical transmission unit to obtain a first current; transmitting second polarized light to a second strain gradient region via a second optical transmission unit to obtain a second current, wherein the polarization characteristics of the second polarized light are the same as those of the first polarized light; and obtaining a polarization angle based on the first current and the second current.

[0025] The detection method of the embodiment of the present application is easy to perform, can obtain an accurate polarization angle, and can distinguish between the polarization angle θ and the polarization angle 180°-θ.

[0026] In some embodiments, the method for detecting polarized light further includes: obtaining optical power based on the first current and the second current.

[0027] With such an arrangement, the detection method can synchronously decouple the optical power with simple steps.

[0028] In some embodiments, the step of obtaining the polarization angle includes: obtaining the polarization angle using a polarization angle mapping relationship of a two-dimensional ferroelectric photovoltaic polarimeter. Exemplarily, the step of obtaining the polarization angle includes: obtaining the polarization angle using a polarization light characteristic equation of a two-dimensional ferroelectric photovoltaic polarimeter.

[0029] With this arrangement, the polarization angle can be obtained quickly. The method for detecting polarized light can obtain the polarization angle quickly and accurately. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a schematic structural diagram of a two-dimensional ferroelectric photovoltaic polarimeter according to one or more embodiments;

[0031] Figure 2 is a schematic top view of a two-dimensional ferroelectric photovoltaic polarimeter according to one or more embodiments;

[0032] Figure 3 is a schematic flow chart of a method for manufacturing a two-dimensional ferroelectric photovoltaic polarimeter according to one or more embodiments;

[0033] Figure 4 is a schematic structural diagram of a two-dimensional ferroelectric photovoltaic polarimeter according to one or more embodiments;

[0034] Figure 5 is a two-dimensional photocurrent curve graph of a two-dimensional ferroelectric photovoltaic polarimeter according to one or more embodiments;

[0035] Figure 6is a schematic flowchart of a method for detecting polarized light according to one or more embodiments.

[0036] Explanation of reference numerals: 1, substrate; 11, semiconductor layer; 12, insulating layer; 2, supporting layer; 3, ferroelectric layer; 31, first electrode region; 32, first strain gradient region; 33, connecting region; 34, second strain gradient region; 35, second electrode region; 4, electrode pattern; 41, first electrode; 42, second electrode; 50, upper cladding layer; 51, first light transmission portion; 52, second light transmission portion;

[0037] 100. Two-dimensional ferroelectric photovoltaic polarimeter; 200. Input optical path; 300. Current acquisition circuit; 400. Processor. DETAILED DESCRIPTION

[0038] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the connotations of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0039] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "perpendicular", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0040] In this application, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it 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. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0041] In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. For example, the first direction may also be referred to as the second direction, and the second direction may also be referred to as the first direction. In the description of this application, "multiple" means at least two, for example, two, three, etc., unless otherwise clearly and specifically defined.

[0042] In this application, unless otherwise clearly specified and limited, the terms "connected", "connect", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a flexible connection, or a rigid connection along at least one direction; it can be a mechanical connection, or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or directly connected with an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. The terms "install", "set", "fix", etc. can be broadly understood as connection. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0043] The terms "layer" and "region" used in this application refer to a material portion that includes a certain area and has a certain thickness. The layer can extend horizontally, vertically and / or along a tapered surface. A layer can be an area of ​​a uniform or non-uniform continuous structure, and its thickness perpendicular to the extension direction may not be greater than the thickness of the continuous structure. A layer can include multiple layers, which can be multiple stacked layers or multiple layers extending discretely. The shapes of the various areas and layers in the accompanying drawings and their relative sizes and positional relationships are only exemplary and may deviate from the actual ones due to manufacturing tolerances or technical limitations, and the design can be adjusted according to actual needs.

[0044] refer to Figure 1 , Figure 1 FIG2 shows a two-dimensional ferroelectric photovoltaic polarimeter in an embodiment of the present application. In an exemplary embodiment, the two-dimensional ferroelectric photovoltaic polarimeter 100 includes a substrate 1 , a support layer 2 , a ferroelectric layer 3 , an electrode pattern 4 , a first light transmitting portion 51 , and a second light transmitting portion 52 .

[0045] For ease of description, a spatial rectangular coordinate system XYZ is established. Substrate 1 may include a semiconductor layer 11 and an insulating layer 12 stacked along the Z-axis. Semiconductor layer 11 may be made of silicon. Insulating layer 12 may be made of silicon dioxide. Insulating layer 12 may include an upper layer and a lower layer.

[0046] For example, the first light-transmitting portion 51 and the second light-transmitting portion 52 are provided on the substrate 1. The first light-transmitting portion 51 and the second light-transmitting portion 52 may be embedded in the upper layer of the insulating layer 12. The two-dimensional ferroelectric photovoltaic polarimeter 100 may further include an upper cladding layer 50. The first light-transmitting portion 51 and the second light-transmitting portion 52 are configured as an optical waveguide. The upper cladding layer 50 helps the optical waveguide to effectively transmit light.

[0047] The support layer 2 is disposed on the substrate 1 along the Z-axis direction. For example, it is stacked on the upper cladding layer 50. Figure 2 The width direction of the support layer 2 can be parallel to the X-axis direction. The width direction can be referred to as the first direction, and the length direction can be referred to as the second direction. The width dimension of the support layer 2 can be smaller than the length dimension of the support layer 2. The support layer 2 can be rectangular, but is not limited thereto. The left and right sides of the support layer 2 can be parallel.

[0048] The material of the support layer 2 may include h-BN, and both sides of the support layer 2 along the width direction are compressive. Alternatively, the material of the support layer 2 may include at least one of silicon nitride, silicon oxide, and aluminum nitride. These materials have insulating properties and can be processed into the desired pattern using a patterning process. The support layer 2 can ensure support performance and limit the strain gradient of the ferroelectric layer 3.

[0049] The support layer 2 forms steps with the substrate 1 on both sides along the width direction. The left and right sides of the support layer 2 can be perpendicular to the Z-axis direction, or there can be a certain deviation. When configuring the support layer 2, the first light transmission portion 51 and the second light transmission portion 52 can be located on both sides of the support layer 2 along the X-axis direction.

[0050] The ferroelectric layer 3 is disposed on the support layer 2 and the substrate 1. The ferroelectric layer 3 is larger than the support layer 2 along the X-axis, and both ends protrude from the support layer 2. The ferroelectric layer 3 includes a first electrode region 31, a first strain gradient region 32, a connection region 33, a second strain gradient region 34, and a second electrode region 35, which are sequentially connected along the width of the support layer 2.

[0051] The connection region 33 is stacked on the support layer 2. The first electrode region 31 and the second electrode region 35 are both lower than the connection region 33, for example, disposed on the substrate 1 or the upper cladding layer 50. The first electrode region 31 and the second electrode region 35 may sink due to gravity or external force.

[0052] The electrode pattern 4 includes a first electrode 41 and a second electrode 42. The first electrode 41 is electrically connected to the first electrode region 31, for example, stacked on the first electrode region 31, and can press down the first electrode region 31. The second electrode 42 is electrically connected to the second electrode region 35, for example, stacked on the second electrode region 35, and can press down the second electrode region 35.

[0053] The material of the ferroelectric layer 3 is a two-dimensional material. The portion of the ferroelectric layer 3 connected between the first electrode region 31 and the connection region 33 becomes the first strain gradient region 32, and the portion of the ferroelectric layer 3 connected between the connection region 33 and the second electrode region 35 becomes the second strain gradient region 34. The first strain gradient region 32 and the second strain gradient region 34 are both used to achieve the bulk photovoltaic effect. Optionally, the material of the ferroelectric layer 3 includes a two-dimensional transition metal chalcogenide or a binary niobium oxyhalide, ensuring that the first strain gradient region 32 and the second strain gradient region 34 are both used to achieve the flexoelectric photovoltaic effect.

[0054] Specifically, by providing a support layer 2 in conjunction with the substrate 1, the ferroelectric layer 3 is confined to form a first strain gradient region 32 and a second strain gradient region 34. Because the first strain gradient region 32 and the second strain gradient region 34 have different bending directions, their strain gradients are also different. When illuminated by light, the flexoelectric photovoltaic effect is generated, generating photocurrents in opposite directions.

[0055] The first light transmission part 51 is used to transmit polarized light to the first strain gradient zone 32, and can output a first current without the need for external electric field power supply; while the second light transmission part 52 is used to transmit another polarized light to the second strain gradient zone 34. Although this polarized light has the same polarization angle as the previous polarized light, the second current output by the two-dimensional ferroelectric photovoltaic polarimeter 100 is different from the first current.

[0056] By designing two strain gradient regions to receive light independently, the two-dimensional ferroelectric photovoltaic polarimeter 100 can output different currents for light with the same polarization characteristics when used for detection. The two-dimensional ferroelectric photovoltaic polarimeter 100 of the present embodiment can be used for polarized light detection, achieving accurate measurement of polarization angles.

[0057] The two-dimensional ferroelectric photovoltaic polarimeter 100 has a simple structure, requiring no additional optical components for polarization angle detection and no heterojunction for photovoltaic detection, significantly reducing the size and multifunctionality of the polarimeter. It utilizes the linear polarization sensitivity of the strain gradient region for polarization detection; it operates without an external electric field using the bulk photovoltaic effect; and its dimensions are small, reaching hundreds of microns.

[0058] refer to Figure 3 The present application provides a method 1000 for manufacturing a two-dimensional ferroelectric photovoltaic polarimeter, which may include steps S101 to S105.

[0059] Step S101: Provide a substrate 1. The substrate 1 in this step can be a prefabricated substrate. The structure obtained in each step can be a prefabricated structure for a subsequent step. The thickness of the substrate 1 can be 300 nm. In the substrate 1, a silicon dioxide layer is formed on a silicon layer.

[0060] Step S102 , forming a first light transmitting portion 51 and a second light transmitting portion 52 .

[0061] Illustratively, the method can be used to manufacture Figure 1 The two-dimensional ferroelectric photovoltaic polarimeter 100 shown in FIG. Specifically, a light transmission portion can be formed on substrate 1. Substrate 1 can be 3 μm thick. Step S102 may include: depositing 200 nm of silicon nitride using a plasma-enhanced chemical vapor deposition process; then spin-coating photoresist on the surface of the silicon nitride film, patterning the desired waveguide pattern using electron beam lithography; and after development, etching the silicon nitride layer using a reactive ion etching system to achieve pattern transfer, thereby obtaining a first light transmission portion 51 and a second light transmission portion 52 of silicon nitride material; then depositing 200 nm of silicon oxide using a plasma-enhanced chemical vapor deposition process to fill the surface and obtain an insulating layer 12; after removing the photoresist from the surface of the silicon nitride layer, a 1 μm thick silicon oxide is deposited on substrate 1 and the silicon nitride layer as an upper cladding layer 50. The upper cladding layer 50 at least covers the silicon nitride layer, serving as a waveguide upper cladding layer.

[0062] The insulating layer 12 may be formed by combining a silicon oxide layer of a prefabricated substrate and deposited silicon oxide. In other embodiments, the insulating layer 12 may be based solely on a prefabricated substrate, or may be formed on the semiconductor layer 11 during the manufacturing process.

[0063] In some other embodiments, step S103 may be performed instead of step S102 .

[0064] Step S103: Providing a support layer 2. Rectangular h-BN nanosheets can be deposited on substrate 1 via a dry transfer process, illustratively on upper cladding layer 50 and between first light-transmitting portion 51 and second light-transmitting portion 52. The support layer 2 forms steps with respect to substrate 1 on both sides along the width direction, illustratively with respect to upper cladding layer 50.

[0065] Step S104, the ferroelectric layer 3 is disposed on the support layer 2 and the substrate 1. The NbOBr2 nanosheets can be disposed on the h-BN nanosheets using a dry transfer process. The h-BN nanosheets have a certain height, and their two edges apply stress to the NbOBr2 nanosheets, forming two high stress regions, namely the first strain gradient region 32 and the second strain gradient region 34. These two regions correspond to the first light transmission part 51 and the second light transmission part 52, respectively, and are used to receive the transmitted light to realize the bulk photovoltaic effect, serving as the two measurement regions of the two-dimensional ferroelectric photovoltaic polarimeter 100. Under the action of the support layer 2, the ferroelectric layer 3 can be divided into five regions connected in sequence along the width direction. The connection region 33 is stacked on the support layer 2, and the first electrode region 31 and the second electrode region 35 can be disposed on the substrate 1.

[0066] Step S105: Forming the electrode pattern 4. Specifically, the first electrode 41 and the second electrode 42 can be formed simultaneously. A 10nm thick titanium (Ti) layer can be deposited first, followed by a 40nm thick gold (Au) layer. This composite metal layer forms an ohmic contact with the ferroelectric layer 3, providing good electrical conductivity for outputting current signals, strong structural strength, and a long service life.

[0067] The manufacturing method of the embodiment of the present application can manufacture a two-dimensional ferroelectric photovoltaic polarimeter 100. The method 1000 for manufacturing a two-dimensional ferroelectric photovoltaic polarimeter is compatible with silicon photonic chip technology, is easy to integrate, and is easy to implement.

[0068] Combine Figure 4 As shown, Figure 4 FIG2 shows a two-dimensional ferroelectric photovoltaic polarimeter in an embodiment of the present application. The two-dimensional ferroelectric photovoltaic polarimeter 100 can be manufactured based on the above method, wherein step S102 is performed after step S104.

[0069] In some embodiments of the two-dimensional ferroelectric photovoltaic polarimeter 100 , the support layer 2 is provided on the substrate 1 ; the first light transmission portion 51 and the second light transmission portion 52 may be optical fibers, respectively, for transmitting light to the first strain gradient region 32 and the second strain gradient region 34 , respectively.

[0070] The first light-transmitting portion 51 can be closer to the supporting layer 2 relative to the first electrode 41, and the second light-transmitting portion 52 can be closer to the supporting layer 2 relative to the second electrode 42. The portion of the ferroelectric layer 3 near the edge of the supporting layer 2 has greater stress, allowing light to be irradiated at locations with higher strain gradients, facilitating detection.

[0071] The first light transmission portion 51 and the second light transmission portion 52 may be symmetrically arranged relative to the support layer 2 , or may be offset from each other.

[0072] The thickness of the support layer 2 ranges from 80 nm to 200 nm, for example, 100 nm, 150 nm, or 180 nm. The support layer 2 provides sufficient height for the bending of the ferroelectric layer 3, thereby ensuring a supporting effect. Exemplarily, the width of the support layer 2 ranges from 6 μm to 20 μm, for example, 8 μm, 10 μm, 12 μm, 14 μm, 16 μm, or 18 μm. The distance between the two edges of the support layer 2 affects the spacing between the two high-stress regions in the ferroelectric layer 3, ensuring that each high-stress region is well formed.

[0073] The thickness of the ferroelectric layer 3 ranges from 30 nm to 50 nm, for example, 40 nm. This thickness refers to the actual thickness at every point along the two-dimensional material. The two-dimensional material is not too thin, ensuring a strong flexoelectric photovoltaic effect, which facilitates current measurement; it is not too thick, preventing bending difficulties and ensuring ease of fabrication. The ferroelectric layer 3 can be supported by a support layer 2 with a width of 6 μm to 20 μm, allowing high stress to form on both sides. In some cases, the dimensions of the connection region 33 can be close to zero, or it can be assumed that some stress exists in the connection region 33.

[0074] In other embodiments, the stress levels on both sides of the ferroelectric layer 3 may be different, mainly to ensure that the strain gradients are opposite; along the extension direction of the two-dimensional material, generally parallel to the width direction of the support layer 2.

[0075] In other embodiments, the middle region of the ferroelectric layer 3 is concave while the regions on both sides are curved, forming a strain gradient region.

[0076] The material of the ferroelectric layer 3 can be a two-dimensional transition metal oxide, and the operating wavelength of the two-dimensional ferroelectric photovoltaic polarimeter 100 configured in this way is longer. Optionally, the material of the ferroelectric layer 3 is MOS2, and the operating wavelength range is 405nm to 980nm.

[0077] The material of the ferroelectric layer 3 can include binary niobium oxyhalide. Binary niobium oxyhalide has a relatively high anisotropy, resulting in a relatively low error in polarization testing by the two-dimensional ferroelectric photovoltaic polarimeter 100. The two-dimensional ferroelectric photovoltaic polarimeter 100 can be used to detect light in the wavelength range of 300 nm to 450 nm. The material of the ferroelectric layer 3 can be NbOBr2, which has a higher anisotropy ratio and relatively low error in polarization testing. The two-dimensional ferroelectric photovoltaic polarimeter 100 can be used to detect light in the ultraviolet wavelength range of 300 nm to 405 nm. The material of the ferroelectric layer 3 can be NbOBr2 with a b-axis parallel to the width direction, resulting in excellent performance of the two-dimensional ferroelectric photovoltaic polarimeter 100.

[0078] refer to Figure 4 In some embodiments, the two-dimensional ferroelectric photovoltaic polarimeter 100 further includes an input optical path 200 and a current collection circuit 300. The input optical path 200 is coupled to the first light transmission unit 51 and the second light transmission unit 52, respectively, and can sequentially transmit the same light to the two light output units. The current collection circuit 300 is electrically connected to the electrode pattern 4, for example, collecting current from the first electrode 41, while the second electrode 42 is grounded.

[0079] The two-dimensional ferroelectric photovoltaic polarimeter 100 may further include a processor 400. The processor 400 is electrically connected to the current acquisition circuit 300. The processor 400 is configured to calculate the polarization angle of polarized light based on the response current of the first strain gradient region 32 and the response current of the second strain gradient region 34. The processor 400 is also configured to calculate the optical power. The two-dimensional ferroelectric photovoltaic polarimeter 100 can transmit the same light to the first strain gradient region 32 and the second strain gradient region 34, respectively, and accurately obtain the polarization angle and optical power.

[0080] The two-dimensional ferroelectric photovoltaic polarimeter 100 may further include a memory, which may be electrically connected to the processor 400. The memory may store computer programs for execution by the processor 400, and may also be used to store measured data and calculated results.

[0081] refer to Figure 5 , using the two-dimensional ferroelectric photovoltaic polarimeter 100 to measure polarized light of different polarization angles, polarized light incident on the first strain gradient region 32 can obtain light input 1 collection current (unit A), and the same polarized light incident on the second strain gradient region 34 can obtain light input 2 collection current. For example, Figure 4 The first electrode 41 is located on the left side along the X-axis, and the second electrode 42 is located on the right side along the X-axis. The left side can be defined as the positive direction of the X-axis, and the 0° deflection angle of the polarized light can be defined as along the left side.

[0082] When faced with polarized light at two different angles, θ and 180°-θ, the 2D ferroelectric photovoltaic polarimeter 100 of the present embodiment measures two different reference data points. Each reference data point corresponds to polarized light at a uniquely determined polarization angle, preventing confusion between θ and 180°-θ. Figure 5 Only some of the benchmark data points are shown; fewer or more benchmark data may be measured.

[0083] refer to Figure 6 The present application provides a method 2000 for detecting polarized light. The method 2000 can utilize the aforementioned two-dimensional ferroelectric photovoltaic polarimeter 100 or the two-dimensional ferroelectric photovoltaic polarimeter 100 obtained by the aforementioned manufacturing method.

[0084] The method 2000 for detecting polarized light may include a step S110 of measuring reference data. In other embodiments, the step S110 may be performed in advance, for example, as a step of a manufacturing method, and the reference data may be written into a memory.

[0085] Illustratively, the method 2000 for detecting polarized light includes steps S201 to S203.

[0086] In step S201 , a first polarized light is transmitted to the first strain gradient region 32 through the first light transmitting portion 51 to obtain a first current.

[0087] In step S202, the second polarized light is transmitted to the second strain gradient region 34 via the second optical transmission unit 52 to generate a second current. The polarization characteristics of the second polarized light are the same as those of the first polarized light. Optionally, the first polarized light and the second polarized light have the same characteristics, for example, they are the front and back segments of the same polarized light beam. Steps S201 and S202 are not performed simultaneously and are not limited in order.

[0088] Step S203, obtaining a polarization angle according to the first current and the second current. Exemplarily, the step of obtaining the polarization angle includes: obtaining the polarization angle using the polarization angle mapping relationship of the two-dimensional ferroelectric photovoltaic polarimeter 100. Figure 5 After the horizontal and vertical coordinates are confirmed, the coordinate points can be mapped to the corresponding polarization angles. The detection method of the embodiment of the present application is easy to perform, can obtain accurate polarization angles, and can distinguish between polarization angles θ and polarization angles 180°-θ.

[0089] For example, the step of obtaining the polarization angle may include: obtaining the polarization angle using a polarization characteristic equation of the two-dimensional ferroelectric photovoltaic polarimeter 100. The equation may be:

[0090] ;

[0091] ;

[0092] in, is the first current, is the second current, 、 、 、 are coefficients based on the two-dimensional ferroelectric photovoltaic polarimeter 100, which can be obtained based on the benchmark data and then become known quantities when using the equation for calculation. By solving the equation, the polarization angle can be obtained ; In addition, the optical power of polarized light can be obtained by solving the equation The detection method of the embodiment of the present application can quickly obtain the polarization angle. The method 2000 for detecting polarized light can quickly and accurately obtain the polarization angle.

[0093] refer to Figure 6 Method 2000 for detecting polarized light further includes step S204 of obtaining optical power based on the first current and the second current. This detection method can simultaneously decouple optical power and is simple. The two-dimensional ferroelectric photovoltaic polarimeter 100 can be used to decouple optical power and polarization angle, achieving multifunctional integration.

[0094] The technical features of the embodiments disclosed above can 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.

[0095] In the embodiments disclosed above, unless otherwise expressly specified and limited, the order of execution of the steps is not limited. For example, the steps may be executed in parallel or in a different order. The substeps of each step may also be executed in an interleaved manner. The various forms of the above-mentioned processes may be used, and steps may be reordered, added, or deleted. As long as the desired results of the technical solutions provided in this application can be achieved, this application is not limited here.

[0096] The embodiments disclosed above merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent protection of the present application. It should be noted that a person skilled in the art could make several variations and improvements without departing from the concept of the present application, all of which fall within the scope of the patent protection claimed by the present application. Therefore, the scope of the patent protection of the present application shall be subject to the appended claims.

Claims

1. A two-dimensional ferroelectric photovoltaic polarimeter, characterized in that include: substrate; a support layer, disposed on the substrate, wherein two sides of the support layer along the width direction respectively form steps with the substrate; a ferroelectric layer comprising a first electrode region, a first strain gradient region, a connection region, a second strain gradient region, and a second electrode region sequentially connected along the width direction, wherein the connection region is stacked on the support layer, and the first electrode region and the second electrode region are disposed on the substrate. The material of the ferroelectric layer is a two-dimensional material, so that the first strain gradient region and the second strain gradient region are both used to achieve a bulk photovoltaic effect; an electrode pattern, comprising a first electrode electrically connected to the first electrode region and a second electrode electrically connected to the second electrode region; a first light transmitting portion, configured to transmit polarized light to the first strain gradient region; as well as The second light transmission part is used to transmit light with the same polarization as the polarized light to the second strain gradient region, wherein the two-dimensional ferroelectric photovoltaic polarimeter is used to calculate the polarization angle of the polarized light based on the response current of the first strain gradient region and the response current of the second strain gradient region.

2. The two-dimensional ferroelectric photovoltaic polarimeter according to claim 1, characterized in that The material of the ferroelectric layer includes binary niobium oxyhalide; the material of the support layer includes at least one of h-BN, silicon nitride, silicon oxide and aluminum nitride.

3. The two-dimensional ferroelectric photovoltaic polarimeter according to claim 2, characterized in that The material of the ferroelectric layer is NbOBr2 with its b-axis parallel to the width direction.

4. The two-dimensional ferroelectric photovoltaic polarimeter according to claim 1, characterized in that The thickness of the ferroelectric layer ranges from 30nm to 50nm; the thickness of the support layer ranges from 80nm to 200nm, and the size of the support layer along the width direction ranges from 6μm to 20μm; the first light transmitting part is close to the support layer relative to the first electrode, and the second light transmitting part is close to the support layer relative to the second electrode.

5. The two-dimensional ferroelectric photovoltaic polarimeter according to claim 1, characterized in that: The first light transmission portion and the second light transmission portion are optical waveguides respectively provided on the substrate, and the two-dimensional ferroelectric photovoltaic polarimeter further includes an upper cladding layer covering the optical waveguides.

6. The two-dimensional ferroelectric photovoltaic polarimeter according to any one of claims 1 to 5, characterized in that: It also includes an input optical path, a current collection circuit and a processor, wherein the input optical path is coupled to the first optical transmission part and the second optical transmission part respectively, the current collection circuit is electrically connected to the electrode pattern, and the processor is electrically connected to the current collection circuit. The processor is configured to calculate the polarization angle of the polarized light and the optical power based on the response current of the first strain gradient region and the response current of the second strain gradient region.

7. A method for manufacturing a two-dimensional ferroelectric photovoltaic polarimeter according to any one of claims 1 to 6, characterized in that include: providing a substrate; forming a first light transmitting portion and a second light transmitting portion; providing a support layer, wherein both sides of the support layer along the width direction form steps with the substrate; A ferroelectric layer is disposed on the support layer and the substrate, wherein the ferroelectric layer includes a first electrode region, a first strain gradient region, a connection region, a second strain gradient region, and a second electrode region sequentially connected along a width direction, the connection region is stacked on the support layer, the first electrode region and the second electrode region are disposed on the substrate, the material of the ferroelectric layer is a two-dimensional material, so that the first strain gradient region and the second strain gradient region are both used to achieve a bulk photovoltaic effect; the first light transmission portion is used to transmit light to the first strain gradient region, and the second light transmission portion is used to transmit light to the second strain gradient region; and An electrode pattern is formed, the electrode pattern including a first electrode electrically connected to the first electrode region and a second electrode electrically connected to the second electrode region.

8. A method for detecting polarized light, characterized in that A two-dimensional ferroelectric photovoltaic polarimeter obtained by using the two-dimensional ferroelectric photovoltaic polarimeter according to any one of claims 1 to 6 or the steps of the method according to claim 7, wherein the method comprises: transmitting a first polarized light to the first strain gradient region through the first light transmitting portion to obtain a first current; transmitting a second polarized light to the second strain gradient region through the second light transmitting portion to obtain a second current, wherein the polarization characteristic of the second polarized light is the same as the polarization characteristic of the first polarized light; and A polarization angle is obtained according to the first current and the second current.

9. The method for detecting polarized light according to claim 8, wherein: Also includes: Optical power is obtained according to the first current and the second current.

10. The method for detecting polarized light according to claim 8 or claim 9, characterized in that: The step of obtaining the polarization angle comprises: The polarization angle is obtained by using a polarization angle mapping relationship of the two-dimensional ferroelectric photovoltaic polarimeter, or by using a polarization light characteristic equation of the two-dimensional ferroelectric photovoltaic polarimeter.

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