A polymer cholesteric liquid crystal laser and a preparation method and an optical device thereof

Abstract

The application discloses a polymer cholesteric liquid crystal laser and a preparation method and optical equipment thereof. The polymer cholesteric liquid crystal laser comprises a laser main body, the laser main body comprises a light-transmitting conductive substrate, a polymer cholesteric liquid crystal layer, a noble metal reflection layer and a resonant cavity unit; the light-transmitting conductive substrate is provided with a parallel orientation layer; the polymer cholesteric liquid crystal layer is arranged on the surface of the parallel orientation layer; the noble metal reflection layer is arranged opposite to the polymer cholesteric liquid crystal layer; the resonant cavity unit is arranged between the noble metal reflection layer and the polymer cholesteric liquid crystal layer; the resonant cavity unit is filled with a planar light waveguide; the planar light waveguide comprises a perovskite quantum dot layer and a transparent separation layer; the transparent separation layer is arranged on the perovskite quantum dot layer and faces two surfaces of the polymer cholesteric liquid crystal layer and the noble metal reflection layer. Through the above structural design, the polymer cholesteric liquid crystal laser has low laser threshold, high radiation intensity and good repeatability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lasers, in particular to a polymer cholesteric liquid crystal laser, a preparation method thereof and an optical device. BACKGROUND

[0002] A laser generally consists of three parts: a pump source, a resonant cavity and a gain medium. The gain medium is generally a luminescent dye or a semiconductor luminescent material. The pump source serves as an external energy source to cause the gain medium to produce particle number inversion. The resonant cavity selects light of a certain frequency wavelength for gain amplification. When the gain of the generated light is greater than the threshold of loss, the laser can produce laser emission. The most commonly used laser is a semiconductor laser. However, the semiconductor laser has poor temperature characteristics, the output light is easy to diverge, and noise is easy to produce, which makes it unsuitable for use in some occasions. In contrast, cholesteric liquid crystal, as a one-dimensional photonic crystal, has the characteristic of Bragg reflection, and can selectively reflect light of a specific wavelength. The cholesteric liquid crystal laser prepared on this principle has the advantages of high stability and large tuning range, and can solve some shortcomings of semiconductor lasers. However, the gain medium of the liquid crystal laser is generally a luminescent dye such as DCM and PM597. However, ordinary luminescent dyes can make the laser threshold of the polymer stable liquid crystal laser high and the emission intensity low. Although the recently researched perovskite quantum dot doped liquid crystal laser can solve the problem of high laser threshold, the dispersibility of the perovskite quantum dots doped into the cholesteric liquid crystal is poor, and the repeatability of the device is low. SUMMARY

[0003] The present application aims to at least solve one of the problems in the prior art. To this end, the present application proposes a polymer cholesteric liquid crystal laser, a preparation method thereof and an optical device.

[0004] In a first aspect of the present application, a polymer cholesteric liquid crystal laser is provided, comprising a laser body, wherein the laser body comprises:

[0005] A light-transmitting conductive substrate having a parallel orientation layer thereon;

[0006] A first reflective layer, the first reflective layer being a polymer cholesteric liquid crystal layer, the first reflective layer being arranged on a surface of the parallel orientation layer;

[0007] A second reflective layer, the second reflective layer being a noble metal reflective layer, the second reflective layer being arranged opposite to the first reflective layer with a spacing therebetween;

[0008] A resonant cavity unit is arranged between the first reflective layer and the second reflective layer, and the resonant cavity unit is filled with a planar light waveguide, which comprises a perovskite quantum dot layer and a transparent separation layer arranged on two surfaces of the perovskite quantum dot layer and facing the first reflective layer and the second reflective layer.

[0009] The polymer cholesteric liquid crystal laser according to the embodiment of the present application has at least the following beneficial effects: when the polymer cholesteric liquid crystal laser is used in combination with a pump source, if the wavelength of the amplified spontaneous emission (ASE) excited by the pump source is just overlapped with the reflection band of the polymer cholesteric liquid crystal layer, the radiation of the ASE is reflected by the Bragg reflection of the polymer cholesteric liquid crystal layer, the reflected light further excites the perovskite quantum dots to generate stimulated radiation, and then the optical gain is continuously achieved, and when the generated optical gain is greater than the optical loss caused by reflection and refraction in the device, laser emission is realized. Moreover, the perovskite quantum dot layer in the polymer cholesteric liquid crystal laser has a high fluorescence quantum yield (up to 50-100%), which can make it easier to generate ASE and correspondingly easier to generate laser emission, thereby resulting in a higher emission intensity and a lower laser threshold of the laser, and the radiation threshold is lower than that of a common semiconductor laser. In addition, the polymer cholesteric liquid crystal layer as the first reflective layer and the noble metal reflective layer as the second reflective layer have a higher reflectivity than the polymer cholesteric liquid crystal layer, and the difference in reflectivity between the two reflective layers makes it unnecessary to specially design the reflectivity of the two reflective layers. Through the above structural design, the laser threshold of the polymer cholesteric liquid crystal laser can be as low as 0.14 mJ / cm 2 , the radiation intensity is high, and the repeatability is good.

[0010] In some embodiments of the present application, the material of the perovskite quantum dot layer is CsPbX3 perovskite quantum dots, wherein X is any one of Cl, Cl m Br 3-m , Br, Br m I 3-m , and 0≤m≤3. As a high-performance luminescent material, the all-inorganic CsPbX3 quantum dots have a high fluorescence quantum yield, the threshold of the perovskite quantum dot film layer for generating ASE is extremely low, the half-width of the radiation light is narrow, can be less than 20 nm, and the monochromaticity and linearity are good.

[0011] The thickness of the resonant cavity unit is generally set to satisfy the resonance formula of the laser. The thickness of the resonant cavity unit is regarded as the optical path L of light propagation. The optical path generally needs to satisfy L = the emitting wavelength / 2 * N, N ≥ 1 and is an integer. In some embodiments of the present application, the thickness of the resonant cavity unit is an integer multiple of half of the light emitting peak wavelength of the CsPbX3 perovskite quantum dot. The light emitting peak wavelength of the CsPbX3 perovskite quantum dot is generally 400-700 nm.

[0012] The thickness of the laser body is generally controlled to be 1.0-2.0 cm. The light-transmitting and conductive substrate, the first reflective layer, the resonant cavity unit and the second reflective layer in the laser body are generally stacked in parallel.

[0013] In some embodiments of the present application, the polymer cholesteric liquid crystal layer is formed by ultraviolet polymerization of a liquid crystal mixture including a liquid crystal monomer, a chiral dopant, a surfactant and a photoinitiator; preferably, the liquid crystal mixture includes 80-95 parts by mass of the liquid crystal monomer, 1-8 parts by mass of the chiral dopant, 1-5 parts by mass of the surfactant and 0.01-1 part by mass of the photoinitiator. The liquid crystal monomer can be HCM-009, HCM-008, HCM-006, 5CB, etc., the chiral dopant can be RM257, S81, R811, S5011, R5011, etc., the photoinitiator can be Irg651, and the surfactant can be 2-methacrylate. The cholesteric liquid crystal with chirality is formed from the liquid crystal monomer and the chiral dopant. The photoinitiator initiates polymerization of the liquid crystal monomer to form a polymer network under ultraviolet irradiation, thereby forming the polymer cholesteric liquid crystal. Since the polymer cholesteric liquid crystal layer has chirality, the laser emitted from the polymer cholesteric liquid crystal layer with low reflectivity also has chirality.

[0014] The noble metal reflective layer has high reflectivity. In some embodiments of the present application, the material of the noble metal reflective layer is selected from at least one of gold and silver, and is preferably silver.

[0015] The transparent separation layer can separate the perovskite quantum dot layer from the first reflective layer and the second reflective layer on both sides. In some embodiments of the present application, the material of the transparent separation layer is selected from at least one of lithium fluoride and aluminum trioxide.

[0016] In some embodiments of the present application, the laser body further includes a spacing module, the spacing module abuts against the first reflective layer and the second reflective layer to form a containing space, and the containing space is used to contain the resonant cavity unit. The material of the spacing module can be lithium fluoride (LiF), and the spacing module specifically wraps the perovskite quantum dot layer from the periphery of the perovskite quantum dot layer between the first reflective layer and the second reflective layer.

[0017] In some embodiments of the present application, the polymer cholesteric liquid crystal laser further comprises a pump source for providing pump energy to the laser body.

[0018] In a second aspect of the present application, a method for preparing any of the polymer cholesteric liquid crystal lasers as described in the first aspect of the present application is provided, comprising the following steps:

[0019] S1, preparing a light-transmitting conductive substrate with a parallel orientation layer; specifically, spin-coating an alignment layer material (such as polyvinyl alcohol) on the light-transmitting conductive substrate, and then performing parallel orientation to obtain the light-transmitting conductive substrate with the parallel orientation layer;

[0020] S2, preparing a polymer cholesteric liquid crystal layer on the parallel orientation layer; specifically, spin-coating a liquid crystal mixture comprising liquid crystal monomers, chiral dopants, surfactants and photoinitiators on the parallel orientation layer, and then performing ultraviolet irradiation polymerization to form the polymer cholesteric liquid crystal layer; alternatively, the light-transmitting conductive substrate with the parallel orientation layer prepared in step S1 can be arranged in parallel with another light-transmitting conductive substrate at a certain interval to form a liquid crystal cell, and then the liquid crystal cell is filled with the liquid crystal mixture comprising liquid crystal monomers, chiral dopants, surfactants and photoinitiators, followed by ultraviolet irradiation of the liquid crystal cell, and then the liquid crystal cell is subjected to freezing and disassembling operation to obtain the polymer cholesteric liquid crystal layer;

[0021] S3, arranging a first transparent separation layer on the polymer cholesteric liquid crystal layer, and then spin-coating perovskite quantum dots on the first transparent separation layer, and annealing and solidifying to form a perovskite quantum dot layer;

[0022] S4, arranging a second transparent separation layer on the perovskite quantum dot layer, and then arranging a noble metal reflective layer on the second transparent separation layer.

[0023] In a third aspect of the present application, an optical device comprising any of the polymer cholesteric liquid crystal lasers as described in the first aspect of the present application is provided. The optical device can be an optical device using the above polymer cholesteric liquid crystal laser in the fields of photonic integration, fiber communication, biological detection and optical sensing. BRIEF DESCRIPTION OF DRAWINGS

[0024] The present application will be further described below in conjunction with the drawings and examples, in which:

[0025] Figure 1 Structure schematic diagram of the polymer cholesteric liquid crystal laser prepared in Example 1;

[0026] Figure 2 Schematic diagram of stimulated radiation of the polymer cholesteric liquid crystal laser of Example 1 under excitation of the pump source laser.

[0027] Reference signs: light-transmitting conductive substrate 100, parallel orientation layer 110, first reflective layer 200, planar light waveguide 300, first transparent separation layer 310, perovskite quantum dot layer 320, second transparent separation layer 330, second reflective layer 400. DETAILED DESCRIPTION

[0028] The concept and the technical effects of the present application will be described clearly and completely in combination with the embodiments below, so as to fully understand the purposes, features and effects of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments of the present application, other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0029] Embodiment 1

[0030] A polymer cholesteric liquid crystal laser is prepared in this embodiment, which can output green laser. The specific preparation process includes:

[0031] S1, under yellow light conditions, 93.35 parts by mass of liquid crystal monomer HCM-006, 3.26 parts by mass of chiral dopant RM257, 1 part by mass of surfactant 2-methyl acrylate and 1 part by mass of photoinitiator IRG651 (benzoin dimethyl ether) were respectively dissolved in 1.1% by mass of dimethylbenzene, stirred uniformly at 40℃ in a brown bottle for 1h, and a liquid crystal mixture was prepared;

[0032] S2, a clean and light-transmitting indium tin oxide conductive glass substrate (ITO substrate) was taken, 5 parts by mass of polyvinyl alcohol aqueous solution was spin-coated, annealed at 60℃ for 1h, after cooling to room temperature, the transparent substrate coated with polyvinyl alcohol aqueous solution was rubbed in one direction with swan black velvet, to form a light-transmitting conductive substrate with a parallel orientation layer;

[0033] S3, the liquid crystal mixture prepared in step S1 was spin-coated on the parallel orientation layer of the light-transmitting conductive substrate prepared in step S2 at a speed of 1000rpm, and the spin-coating time was 30s, and then the light-transmitting conductive substrate spin-coated with the liquid crystal mixture was cured under ultraviolet light, to form a polymer cholesteric liquid crystal layer on the light-transmitting conductive substrate as a first reflective layer;

[0034] S4. Take a certain amount of LiF target material and deposit it onto the polymer cholesteric liquid crystal layer with a thickness controlled at about 50 nm to form a first transparent separator layer (LiF layer); then spin-coat or drop-coat a layer of CsPbBr3 perovskite quantum dots with a thickness of 160*N (N is an integer greater than or equal to 1) nm on the first transparent separator layer, and anneal it to form a perovskite quantum dot layer; then deposit a layer of LiF with a thickness of 50 nm on the perovskite quantum dot layer to form a second transparent separator layer; the first transparent separator layer, the perovskite quantum dot layer and the second transparent separator layer are combined to form a planar optical waveguide;

[0035] S5. A 50nm thick layer of silver is deposited on the second transparent separator layer to form a silver reflective layer as the second reflective layer, thus obtaining a polymer cholesteric liquid crystal laser with a multilayer structure.

[0036] The structure of the polymer cholesteric liquid crystal laser prepared by the above method is as follows: Figure 1 As shown, it includes a laser body, which comprises a transparent conductive substrate 100, a first reflective layer 200, a second reflective layer 400, and a resonant cavity unit. A parallel alignment layer 110 is disposed on the transparent conductive substrate 100. The first reflective layer 200 is a polymer cholesteric liquid crystal layer disposed on the parallel alignment layer 110. The second reflective layer 400 is a silver reflective layer, and is disposed opposite to the first reflective layer 200 at a distance. The resonant cavity unit is sandwiched between the first reflective layer 200 and the second reflective layer 400. The resonant cavity unit is filled with a planar optical waveguide 300. The planar optical waveguide 300 includes a first transparent separator layer 310, a perovskite quantum dot layer 320, and a second transparent separator layer 330. The first transparent separator layer 310 is sandwiched between the perovskite quantum dot layer 320 and the first reflective layer 200 to separate the perovskite quantum dot layer 320 and the first reflective layer 200. The second transparent separator layer 330 is sandwiched between the perovskite quantum dot layer 320 and the second reflective layer 400 to separate the perovskite quantum dot layer 320 and the second reflective layer 400.

[0037] See Figure 2 When the polymer-cholesterol liquid crystal laser is stimulated by an external pump pulse laser, the perovskite quantum dot layer 320 in the laser undergoes stimulated absorption. Electrons in the quantum dots at low energy levels absorb energy supplied by the pump source and transition to higher energy levels, thus causing population inversion. At this time, the quantum dots with emission wavelengths within the photonic bandgap of the polymer-cholesterol liquid crystal generate ASE, and the intensity of the emitted light increases. Under the dual effects of Bragg reflection and silver reflection layer in the polymer-cholesterol liquid crystal layer, the emitted light is further amplified, thus generating stimulated emission. The emitted laser light exits from the liquid crystal thin film layer with low reflectivity.

[0038] In some embodiments, after the polymer cholesteric liquid crystal layer is prepared in step S3, a spacer template can be arranged at the edge of the polymer cholesteric liquid crystal layer, a containing space is formed by the spacer template and the polymer cholesteric liquid crystal layer, then a planar light waveguide 300 is arranged in the containing space, the planar light waveguide 300 contained in the containing space constitutes a resonant cavity unit, and a silver reflective layer is arranged on the end of the spacer template away from the polymer cholesteric liquid crystal layer, thereby preparing a polymer cholesteric liquid crystal laser. The thickness of the resonant cavity unit can be controlled to be an integer multiple of half of the light emission peak wavelength (400-700 nm) of the CsPbX3 perovskite quantum dot, and the thickness of the laser body is generally controlled to be 1.0-2.0 cm. In addition, the silver reflective layer can also be replaced by other noble metal reflective layers. In addition to lithium fluoride (LiF), the transparent separation layer can also be prepared by using aluminum oxide.

[0039] Embodiment 2

[0040] In this embodiment, a polymer cholesteric liquid crystal laser is prepared, which can output blue laser, and the specific preparation process comprises:

[0041] S1, under yellow light conditions, 93.1 parts by mass of liquid crystal monomer HCM-006, 3.56 parts by mass of chiral dopant RM257, 1 part by mass of surfactant 2-methyl acrylate and 1 part by mass of photoinitiator IRG651 (benzoin dimethyl ether) are dissolved in 1.1% by mass of dimethylbenzene, stirred uniformly at 40°C in a brown bottle for 1 h, and a liquid crystal mixture is prepared;

[0042] S2, a clean and transparent indium tin oxide conductive glass substrate (ITO substrate) is taken, 5 parts by mass of polyvinyl alcohol aqueous solution is spin-coated, annealed at 60°C for 1 h, after cooling to room temperature, the transparent substrate coated with polyvinyl alcohol aqueous solution is rubbed along one direction with a swan black velvet cloth to form a transparent conductive substrate with a parallel orientation layer;

[0043] S3, a layer of liquid crystal mixture prepared in step S1 is spin-coated on the parallel orientation layer of the transparent conductive substrate prepared in step S2 at a speed of 1000 rpm, and the spin-coating time is 30 s; then the transparent conductive substrate spin-coated with the liquid crystal mixture is cured under ultraviolet light to form a polymer cholesteric liquid crystal layer on the transparent conductive substrate as a first reflective layer;

[0044] S4, take a certain amount of LiF target material, evaporate it on the polymer cholesteric liquid crystal layer, the thickness is controlled to be about 50 nm, to form a first transparent separation layer (LiF layer); then spin coating or drop coating a layer of CsPbCl3 perovskite quantum dots with a thickness of 140*N (N is an integer greater than or equal to 1) nm on the first transparent separation layer, and performing annealing treatment to form a perovskite quantum dot layer; then evaporating a layer of LiF with a thickness of 50 nm on the perovskite quantum dot layer to form a second transparent separation layer; the first transparent separation layer, the perovskite quantum dot layer and the second transparent separation layer are combined to form a planar optical waveguide;

[0045] S5, evaporate a layer of silver with a thickness of 50 nm on the second transparent separation layer to form a silver reflection layer as a second reflection layer, and obtain a polymer cholesteric liquid crystal laser with a multilayer structure.

[0046] Example 3

[0047] In this embodiment, a polymer cholesteric liquid crystal laser is prepared, which can output red laser light, and the specific preparation process comprises:

[0048] S1, under yellow light conditions, 95.0 parts by mass of liquid crystal monomer HCM-006, 3.0 parts by mass of chiral dopant RM257, 1 part by mass of surfactant 2-methacrylate ethyl ester and 1 part by mass of photoinitiator IRG651 (benzoin dimethyl ether) are respectively dissolved in 1.1% by mass of dimethylbenzene, stirred uniformly at 40°C in a brown bottle for 1h, and a liquid crystal mixture is prepared;

[0049] S2, take a clean and transparent indium tin oxide conductive glass substrate (ITO substrate), spin coating 5 parts by mass of polyvinyl alcohol aqueous solution, annealing at 60°C for 1h, and after cooling to room temperature, rubbing the transparent substrate coated with polyvinyl alcohol aqueous solution along one direction with a swan black velvet cloth to form a transparent conductive substrate with a parallel orientation layer;

[0050] S3, spin coating a layer of the liquid crystal mixture prepared in step S1 on the parallel orientation layer of the transparent conductive substrate prepared in step S2 at a speed of 1000 rpm, and the spin coating time is 30s; then curing the transparent conductive substrate coated with the liquid crystal mixture under ultraviolet light conditions, and forming a polymer cholesteric liquid crystal layer on the transparent conductive substrate as a first reflection layer;

[0051] S4, a certain amount of LiF target material is taken and evaporated on the polymer cholesteric liquid crystal layer to form a first transparent separation layer (LiF layer) with a thickness of about 50 nm; then a layer of CsPbI3 perovskite quantum dots with a thickness of 140*N (N is an integer greater than or equal to 1) nm is spin-coated or drop-coated on the first transparent separation layer, and annealing treatment is performed to form a perovskite quantum dot layer; then a layer of LiF with a thickness of 50 nm is evaporated on the perovskite quantum dot layer to form a second transparent separation layer; the first transparent separation layer, the perovskite quantum dot layer and the second transparent separation layer combine to form a planar optical waveguide;

[0052] S5, a layer of silver with a thickness of 50 nm is evaporated on the second transparent separation layer to form a silver reflection layer as a second reflection layer, thereby obtaining a polymer cholesteric liquid crystal laser with a multi-layer structure.

[0053] The polymer cholesteric liquid crystal laser obtained in each of the above embodiments can be used in cooperation with a pump source. When the radiation wavelength of the amplified spontaneous emission (ASE) excited by the pump source on the perovskite quantum dot layer just overlaps with the reflection band of the polymer cholesteric liquid crystal layer, the radiation light generated by the amplified spontaneous emission will be reflected by the Bragg reflection of the polymer cholesteric liquid crystal layer, the reflected light will further excite the perovskite quantum dots to generate stimulated radiation, and then the light gain will be continuously achieved. When the generated light gain is greater than the light loss caused by reflection and refraction in the device, laser emission can be realized. Moreover, the perovskite quantum dot layer in the polymer cholesteric liquid crystal laser has a high fluorescence quantum yield (up to 50-100%), which can make it easier to generate ASE, and accordingly, it is easier to generate laser emission, thereby resulting in a laser with higher emission intensity and lower laser threshold. In addition, the polymer cholesteric liquid crystal layer as the first reflection layer and the noble metal reflection layer as the second reflection layer have a higher reflectivity than the polymer cholesteric liquid crystal layer, and the difference in reflectivity between the two reflection layers makes it unnecessary to specially design the reflectivity difference between the two reflection layers. Through the above structural design, the polymer cholesteric liquid crystal laser has a low laser threshold, high radiation intensity and good repeatability. In some embodiments, the polymer cholesteric liquid crystal laser can also include a pump source itself, which is used to provide pump energy to the laser body. In addition, the above polymer cholesteric liquid crystal laser can be applied to the preparation of optical equipment in the fields of photonic integration, optoelectronic communication, biological detection and optical sensing, and therefore, the present application also provides another optical equipment comprising any one of the above polymer cholesteric liquid crystal lasers.

[0054] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are within the protection scope of the present application.

Claims

1. A polymeric cholesteric liquid crystal laser, characterized in that, The laser body includes a light-transmitting conductive substrate having a parallel alignment layer. A first reflective layer, wherein the first reflective layer is a polymeric cholesteric liquid crystal layer, and the first reflective layer is disposed on the surface of the parallel alignment layer; The second reflective layer is a noble metal reflective layer. The second reflective layer is disposed opposite to the first reflective layer at a distance. The reflectivity of the second reflective layer is higher than that of the first reflective layer. A resonant cavity unit is sandwiched between the first reflective layer and the second reflective layer. The resonant cavity unit is filled with a planar optical waveguide, which includes a perovskite quantum dot layer and a transparent separator layer. The transparent separator layer is disposed on two surfaces of the perovskite quantum dot layer facing the first and second reflective layers. The transparent separator layer is made of lithium fluoride and has a thickness of 50 nm. The perovskite quantum dot layer is made of CsPbX3 perovskite quantum dots, where X represents Cl or Cl₂. m Br 3-m Br, Br m I 3-m Any of I and I, 0≤m≤3; The laser body also includes a spacer module, which abuts against the first reflective layer and the second reflective layer to form an accommodating space for accommodating the resonant cavity unit; the spacer module is made of lithium fluoride, and the spacer module circumferentially covers the perovskite quantum dot layer between the first reflective layer and the second reflective layer with a titanium dioxide quantum dot layer.

2. The polymer cholesteric liquid crystal laser according to claim 1, characterized in that, The thickness of the resonant cavity unit is an integer multiple of half the emission peak wavelength of the CsPbX3 perovskite quantum dot.

3. The polymer cholesteric liquid crystal laser according to claim 1, characterized in that, The polymeric cholesteric liquid crystal layer is formed by ultraviolet light polymerization of a liquid crystal mixture including liquid crystal monomers, chiral dopants, surfactants and photoinitiators.

4. The polymer cholesteric liquid crystal laser according to claim 3, characterized in that, The liquid crystal mixture comprises 80-95 parts by weight of liquid crystal monomer, 1-8 parts by weight of chiral dopant, 1-5 parts by weight of surfactant, and 0.01-1 parts by weight of photoinitiator.

5. The polymer cholesteric liquid crystal laser according to claim 1, characterized in that, The material of the precious metal reflective layer is selected from at least one of gold and silver.

6. The polymer cholesteric liquid crystal laser according to any one of claims 1 to 5, characterized in that, It also includes a pump source for providing pump energy to the laser body.

7. The method for preparing the polymer cholesteric liquid crystal laser according to any one of claims 1 to 6, characterized in that, Includes the following steps: S1. Prepare a transparent conductive substrate with a parallel alignment layer; S2. Prepare a polymeric cholesteric liquid crystal layer on the parallel orientation layer; S3. A spacer template is provided at the edge of the polymer cholesteric liquid crystal layer, and the spacer template and the polymer cholesteric liquid crystal layer are used to form an accommodating space. A first transparent separator layer is formed on the polymer cholesteric liquid crystal layer, and then perovskite quantum dots are spin-coated on the first transparent separator layer and annealed and cured to form a perovskite quantum dot layer. S4. A second transparent separator layer is disposed on the perovskite quantum dot layer, and then a noble metal reflective layer is disposed on the second transparent separator layer at the end of the spacer template facing away from the polymer cholesteric liquid crystal layer.

8. An optical device, characterized in that, The polymer cholesteric liquid crystal laser includes any one of claims 1 to 6.

Images