Multi-polarization detector based on perovskite superstructure surface and preparation method and photoelectric detection method thereof

Abstract

The application provides a multi-polarized light photodetector based on a perovskite superstructure surface, the perovskite is directly prepared into a superstructure surface, the perovskite superstructure surface has different absorption to different polarized light, and the difference in the absorption leads to the difference in photocurrent, so that the detection of linearly polarized light and circularly polarized light can be simultaneously realized through light absorption and photocurrent measurement. Further, the application also discloses a photodetection method based on the multi-polarized light photodetector and a preparation method of the multi-polarized light photodetector.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of optical devices, and particularly relates to a multi-polarization photodetector and a preparation method thereof. BACKGROUND

[0002] Optical polarization detection has been applied in many different fields, including communication, optical switch, near-field imaging and biosensor, etc. So far, several different electronic devices have been proposed to effectively detect and distinguish the polarization state of light. One approach is to use polarization-sensitive semiconductor materials as active layers to detect linearly polarized light or circularly polarized light, which have inherent in-plane anisotropy or chirality, including some two-dimensional materials and chiral organic semiconductors, etc., but the types of these materials are limited after all. In addition, it has also been proved that the composite structure combining plasmonic superstructures (such as superstructures composed of gold nanometer antennas) with some two-dimensional materials (such as transition metal sulfides, graphene) can detect linearly polarized light or circularly polarized light, in which the superstructures have different resonance absorption enhancement for different polarized light. However, these devices are often affected by metal loss, and their manufacturing process is relatively complex, in addition, the compatibility of metal and material also needs to be considered.

[0003] Hybrid organic-inorganic perovskites have become a promising semiconductor material for the preparation of advanced optoelectronic devices due to their excellent optoelectronic properties, such as high absorption coefficient, high carrier mobility, long carrier diffusion distance, etc. In recent years, perovskite-based photodetectors with polarization response have also developed rapidly. For example, linearly polarized light can be detected by using anisotropically arranged perovskite microcolumns and microlines, and circularly polarized light can be detected by using chiral perovskites. However, these photodetectors can only realize a single function, that is, to detect linearly polarized light or circularly polarized light. This multifunctionality of simultaneously detecting linearly polarized light and circularly polarized light is very important for the miniaturization and integration of optoelectronic devices. SUMMARY

[0004] To solve the above problems, the present application proposes a multi-polarization photodetector, which directly prepares perovskite into a superstructure, and realizes the simultaneous detection of linearly polarized light and circularly polarized light by using the difference in the absorption of different polarized light by the perovskite superstructure, which leads to the difference in photocurrent. Further, the present application also discloses a photodetection method based on the above multi-polarization photodetector and a preparation method of the above multi-polarization photodetector.

[0005] The specific technical solutions of the present application include:

[0006] Scheme one: the application provides a kind of multi-polarization detector based on perovskite superstructure surface, including substrate, perovskite film layer, perovskite superstructure surface and metal electrode;The perovskite film layer is formed on substrate surface;The perovskite superstructure surface is formed on the surface of perovskite film layer, which is composed of a plurality of periodically arranged L-shaped perovskite nanostructures;The metal electrode is arranged on the surface of perovskite film layer and adjacent to the perovskite superstructure surface;The L-shaped perovskite nanostructure has in-plane heterogeneity, and different optical resonance modes can be excited when linearly polarized light of different polarization directions is incident, so that the perovskite superstructure surface has different absorption responses to linearly polarized light of different polarization directions;The L-shaped perovskite nanostructure also has the property of mirror plane asymmetry, and the excited optical resonance modes are also different when left-handed circularly polarized light and right-handed circularly polarized light are incident, so that the perovskite superstructure surface also has different absorption responses to left-handed circularly polarized light and right-handed circularly polarized light.

[0007] As a preferred scheme, the length of the long axis of the L-shaped perovskite nanostructure is 300-400 nm, the length of the short axis is 200-250 nm, the width of the long axis and the short axis is the same and is 50-150 nm;The thickness of the L-shaped perovskite nanostructure is 100-250 nm;The period of the L-shaped perovskite nanostructure is 500-600 nm.

[0008] As a preferred scheme, the thickness of the perovskite film layer is 10-100 nm.

[0009] As a preferred scheme, the material of the perovskite film layer and the perovskite superstructure surface includes methylamine lead iodine, cesium lead iodine or formamidinium lead iodine.

[0010] As a preferred scheme, the material of the metal electrode is gold, silver, copper or aluminum.

[0011] As a preferred scheme, the thickness of the metal electrode is 30-200 nm.

[0012] Scheme two: the application also provides a photoelectric detection method, using the multi-polarization detector of any one of scheme one and its preferred schemes, the metal electrode is connected to the source table, so as to detect and distinguish linearly polarized light of different polarization directions and left-handed circularly polarized and right-handed circularly polarized light by measuring the difference of photoelectric current.

[0013] As a preferred scheme, the linear polarization detection wavelength range is 550-750 nm.

[0014] Scheme three: the application also provides a preparation method for preparing the multi-polarization detector in any one of the schemes one and the preferred schemes thereof, mainly comprising: providing a substrate; growing a perovskite thin film layer on the substrate; preparing a periodic arrangement of L-shaped perovskite nanostructures on the perovskite thin film layer to form a perovskite super-structured surface; and preparing a metal electrode on the perovskite thin film layer.

[0015] As a preferred scheme, the perovskite thin film layer is grown on the substrate using a solution method; the periodic arrangement of L-shaped perovskite nanostructures is prepared on the thin film by ion beam or gas etching; and the metal electrode is prepared on the perovskite thin film layer by electron beam evaporation.

[0016] The application has the following beneficial effects:

[0017] (1) The photoelectric detector prepared by the perovskite super-structured surface has the function of simultaneously detecting linearly polarized light and circularly polarized light.

[0018] (2) In the application, the absorption and photocurrent of the L-shaped perovskite nanostructure for linearly polarized light incident in different directions are different in a wide waveband range, so the linearly polarized light can be wideband detected, and the linearly polarized detection wavelength range can reach 550-750 nm.

[0019] (3) The application is composed of all-dielectric perovskite nanostructures, does not introduce additional metal loss, has a mature sample preparation process, is easy to process, and has low manufacturing cost. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 (a) is a structure schematic diagram of a multi-polarized photoelectric detector based on a perovskite super-structured surface; and (b) is a structure schematic diagram in one period. In the figure, L1, L2, w and p are respectively the long axis length, the short axis length, the width and the period of the L-shaped perovskite nanostructure.

[0021] Figure 2 (a) is a scanning electron microscope image of a perovskite super-structured surface (the scale in the figure is 500 nm); (b) is the transmittance and reflectance spectrum of the sample when linearly polarized light is incident along the x-axis and the y-axis direction; (c) is the absorption spectrum when linearly polarized light is incident along the x-axis and the y-axis direction; (d) is the absorption spectrum when linearly polarized light in different linearly polarized directions is incident; (e) is the transmittance and reflectance spectrum of the sample when left-handed circularly polarized light and right-handed circularly polarized light is incident; and (f) is the absorption spectrum when left-handed circularly polarized light and right-handed circularly polarized light is incident.

[0022] Figure 3(a) is an optical microscope image of the perovskite superstructured surface sample (the scale bar in the figure is 10 μm); (b) is the photocurrent measured when linearly polarized light is incident along the x-axis and along the y-axis; (c) is the time-resolved photocurrent response when linearly polarized light is incident along the x-axis and along the y-axis; (d) is the photocurrent when linearly polarized light of different wavelengths is incident along the x-axis and along the y-axis; (e) is the photocurrent measured when left-handed and right-handed circularly polarized light is incident; (f) is the time-resolved photocurrent response when left-handed and right-handed circularly polarized light is incident.

[0023] Legend: 1 - substrate, 2 - perovskite thin film, 3 - L-shaped perovskite nanostructure, 4 - metal electrode. DETAILED DESCRIPTION

[0024] The application will be further explained in connection with the accompanying drawings and specific embodiments.

[0025] In connection with Figure 1As shown, the application gives a multi-polarization photodetector based on perovskite super-structured surface, which mainly includes substrate 1, perovskite thin layer 2, L-shaped perovskite nanostructure array and metal electrode 4 arranged from bottom to top. Among them: substrate 1 can be prepared by quartz, silicon or alumina material, as long as it can prepare perovskite film on its surface. Perovskite thin film layer 2 is mainly used for the function of carrier transport, and the thickness of perovskite thin film layer 2 can be 10-100 nm. L-shaped perovskite nanostructure array is composed of a plurality of periodically arranged L-shaped perovskite nanostructures 3. The length L1 of the long axis of the L-shaped perovskite nanostructure is 300-400 nm, the length L2 of the short axis is 200-250 nm, the long axis and the short axis adopt equal width design, the width w is 50-150 nm, the thickness of the L-shaped perovskite nanostructure is 100-250 nm, and the period p is 500-600 nm. The length and thickness of the long and short axes of the L-shaped antenna and the size of the period and other parameters will affect the absorption of the super-structured surface. The perovskite material used here only needs to have a difference in absorption at the target wavelength, for example, methylamine lead iodine (MAPbI3), cesium lead iodine (CsPbI3), formamidinium lead iodine (FAPbI3) and the like. Because the L-shaped perovskite nanostructure 3 has in-plane anisotropy, when linearly polarized light with different polarization directions is incident, different optical resonance modes are excited in the L-shaped perovskite nanostructure, so that the perovskite super-structured surface absorbs linearly polarized light with different polarization directions; Because the L-shaped perovskite nanostructure 3 has the property of mirror plane asymmetry, when left-handed circularly polarized light and right-handed circularly polarized light are incident, the optical resonance modes excited in the perovskite super-structured surface are also different, so that the perovskite super-structured surface absorbs left-handed circularly polarized light and right-handed circularly polarized light differently. Further, we design metal electrodes 4 at both ends of the super-structured surface area. The metal electrode 4 can be made of gold, silver, copper or aluminum in a strip structure, and the thickness of the metal electrode 4 is 30-200 nm. Of course, the metal electrode 4 can also be other shapes, which can be used for photocurrent measurement. When different polarized light is incident on the super-structured surface, we measure different photocurrent responses.

[0026] The above-mentioned multi-polarization photodetector based on perovskite super-structured surface can be prepared by the following method: providing a substrate 1; growing a perovskite thin film layer 2 on the surface of the substrate 1 by a solution method; then using ion beam or gas etching or other etching methods to prepare periodic L-shaped perovskite nanostructures on the film; finally, preparing a metal strip electrode on the sample by electron beam evaporation.

[0027] The application will be further explained and described below in conjunction with specific examples and drawings:

[0028] In the embodiment, we first disclose a specific method for preparing a multi-polar photodetector, mainly comprising: first growing a methylamine lead iodine perovskite film on a substrate using a solution method, then preparing a periodic L-shaped perovskite nanostructure on the perovskite film using ion beam etching, the long axis length L1 of the L-shaped perovskite nanostructure is 380±5 nm, the short axis length L2 is 250±5 nm, the thickness is 160±5 nm, the width w is 100±5 nm, the period p is 500±5 nm, and the bottom perovskite film thickness is 15±5 nm; next, a gold electrode with a thickness of 40±5 nm is prepared on the sample by electron beam evaporation using a mask. Through the above method, we obtain a multi-polar photodetector sample. Next, we will test the multi-polar photodetector sample obtained in the embodiment (hereinafter referred to as "sample") accordingly.

[0029] Figure 2 (a) gives the local scanning electron micrograph of the L-shaped perovskite nanostructure array in the sample, where the scale is 500 nm. Figure 2 (b) is the transmittance-reflectance spectrum of the perovskite superstructure surface when linearly polarized light is incident along the x-axis and along the y-axis. We can see that the reflection of the L-shaped perovskite nanostructure region is obviously suppressed, and in the wavelength range of 550-750 nm, the transmittance of the superstructure surface when linearly polarized light is incident along the x-axis is greater than that when linearly polarized light is incident along the y-axis. Figure 2 (c) is the absorption spectrum obtained by formula A = 1-T-R from the transmittance-reflectance spectrum (where A, T, and R represent absorption, transmittance, and reflectance, respectively), which can be seen in the wavelength range of 550-750 nm, the absorption of the perovskite superstructure surface when linearly polarized light is incident along the y-axis is greater than that when linearly polarized light is incident along the x-axis. Figure 2 (d) is the absorption spectrum of the superstructure surface when linearly polarized light is incident in different directions, it can be found that when the polarization direction of the incident light is 0° (θ = 0), the absorption is the smallest, and as the polarization direction increases with the x-axis angle, the absorption reaches a maximum value at 90° (θ = 90), where θ is defined as the angle between the polarization direction of linearly polarized light and the positive direction of the x-axis. Similarly, Figure 2 (e) gives the transmittance-reflectance spectrum of the superstructure surface under left circularly polarized light and right circularly polarized light, it can be seen that the reflection of the L-shaped perovskite nanostructure region is obviously suppressed, and in the wavelength range of 610 nm, the transmittance spectrum of the superstructure surface under left circularly polarized light and right circularly polarized light shows differences. Figure 2(f) is the absorption spectrum obtained by formula A = 1-T-R from the transmittance-reflectance spectrum, which shows that the absorption of the superstructure surface is greater for left circularly polarized light than for right circularly polarized light at a wavelength of about 610 nm. This shows that the perovskite superstructure surface not only has different absorption for linearly polarized light with different polarization directions, but also has different absorption for left and right circularly polarized light.

[0030] Figure 3 (a) shows the optical microscope image of the prepared sample. Figure 3 (b) is the I-V curve of the perovskite superstructure surface measured under linearly polarized light with a wavelength of 700 nm along the x-axis and along the y-axis. When the voltage changes from 0 V to 2 V, the photocurrent generated under linearly polarized light along the y-axis is always greater than that generated under linearly polarized light along the x-axis. In addition, the photocurrent measured under linearly polarized light along the y-axis is greater than that under linearly polarized light along the x-axis in the wavelength range of 550-750 nm, which shows that the perovskite superstructure surface has the performance of broadband linearly polarized light detection, such as Figure 3 (d) shows. Similarly, Figure 3 (e) is the I-V curve of the perovskite superstructure surface measured under left and right circularly polarized light with a wavelength of 610 nm. When the voltage changes from 0 V to 2 V, the photocurrent generated under left circularly polarized light is always greater than that generated under right circularly polarized light. Figure 3 (c) and Figure 3 (f) is the time-resolved photocurrent response measured under periodic modulation of light at a bias voltage of 2 V, Figure 3 (c) is the case of linearly polarized light along the x-axis and linearly polarized light along the y-axis, Figure 3 (f) is the case of left and right circularly polarized light. During the measurement, the incident light is periodically turned on and off, and when it is turned on, a stable photocurrent difference can be observed. This shows that linearly polarized light along the x-axis and linearly polarized light along the y-axis can be detected and distinguished by electrical measurement, and left and right circularly polarized light can be distinguished.

[0031] In summary, the perovskite superstructure surface in the disclosed multi-polarized photodetector sample has different optical absorption and photocurrent responses for linearly polarized light with different polarization directions and left and right circularly polarized light, and can be used for the detection of various polarized light, and is expected to be applied in the fields of polarization imaging, biosensing, etc.

[0032] The above merely provides the preferred embodiments of the present application, and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the principles and technical scope of the present application shall fall into the scope of the present application.

Claims

1. A multi-polarization detector based on perovskite superstructured surface, characterized in that, The application relates to a multi-polarization detector, which comprises a substrate, a perovskite thin film layer, a perovskite superstructure surface and a metal electrode; the perovskite thin film layer is formed on the surface of the substrate; the perovskite superstructure surface is formed on the surface of the perovskite thin film layer and is composed of a plurality of periodically arranged L-shaped perovskite nanostructures; the metal electrode is arranged on the surface of the perovskite thin film layer and is adjacent to the perovskite superstructure surface; the L-shaped perovskite nanostructure has in-plane anisotropy and can excite different optical resonance modes when linearly polarized light with different polarization directions is incident, so that the perovskite superstructure surface has different absorption responses to linearly polarized light with different polarization directions; the L-shaped perovskite nanostructure also has a mirror asymmetric property, and the excited optical resonance modes are also different when left-handed circularly polarized light and right-handed circularly polarized light are incident, so that the perovskite superstructure surface also has different absorption responses to left-handed circularly polarized light and right-handed circularly polarized light.

2. The multi-polarization detector of claim 1, wherein, The length of the long axis of the L-shaped perovskite nanostructure is 300-400 nm, the length of the short axis is 200-250 nm, the width of the long axis and the short axis is the same and is 50-150 nm; the thickness of the L-shaped perovskite nanostructure is 100-250 nm; and the period of the L-shaped perovskite nanostructure is 500-600 nm.

3. The multi-polarization detector of claim 1, wherein, The thickness of the perovskite thin film layer is 10-100 nm.

4. The multi-polar detector of claim 1, wherein, The material of the perovskite thin film layer and the perovskite superstructure surface is methylamine lead iodine, cesium lead iodine or formamidinium lead iodine.

5. The multi-polarization detector of claim 1, wherein, The material of the metal electrode is gold, silver, copper or aluminum.

6. The multi-polar detector of claim 1, wherein, The thickness of the metal electrode is 30-200 nm.

7. A photodetection method, comprising: The application also discloses a method for preparing the multi-polarization detector.

8. The photodetection method of claim 7, wherein, The detection working wavelength range of the linearly polarized light is 550-750 nm.

9. A method of manufacture, characterized by, The application also discloses a method for preparing the multi-polarization detector. The application also discloses a method for preparing the multi-polarization detector. The application also discloses a method for preparing the multi-polarization detector. The application also discloses a method for preparing the multi-polarization detector. ​ 10. The production method according to claim 9, wherein ​

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