CN114976835A - Optically controlled broad-spectrum switchable single-mode laser, preparation method and application thereof - Google Patents

Abstract

The invention discloses a light-operated wide-spectrum switchable single-mode laser and a preparation method and application thereof. The dynamic energy transfer process is realized by taking photochromic molecules with photoisomerization process as receptors; the photoisomerization process is caused by light-induced structural transformation of photochromic molecules, one isomer is used as an energy receptor, and the concentration change of a light-operated receptor can effectively adjust the energy transfer process between the receptors, so that the wide-spectrum adjustable micro-nano laser is realized. The single-mode laser is realized by a coupling resonant cavity, and the coupling resonant cavity can provide optical feedback and mode selection for stimulated radiation of a gain medium to realize the emission of the single-mode laser; the wide-spectrum adjustable single-mode laser is realized by respectively regulating and controlling the energy transfer processes in the two resonant cavities in the coupling structure, so that the adjustment range of laser wavelength is widened, and the controllable switching of double wavelengths in the same system is realized; the wide-spectrum tunable single-mode laser can be used for high-density photonic integration.

Description

Optically controlled broad-spectrum switchable single-mode laser, preparation method and application thereof

technical field

The invention belongs to the technical field of organic micro-nano lasers, and in particular relates to an optically controlled broad-spectrum two-color switchable single-mode laser and a preparation method and application thereof.

Background technique

共振能量转移过程(FRET)可以实现从给体分子到受体分子的能量转移，有效地扩展了激光输出波长的调谐区间，因此有望实现宽谱可切换的激光。然而，通常FRET效率受给体和受体化学计量比控制，一旦体系中激光染料的浓度固定，其输出激光的波长往往恒定，难以基于这种机制实现输出激光波长的动态调控，从而限制了其在可切换激光中的应用。因此，发展一种给受体化学计量比动态可调控的FRET激光系统将十分有利于构筑宽谱可切换的单模微纳激光器。Organic micro-nano lasers have broad application prospects in the fields of biochemical sensing, laser display and integrated photonic circuits due to their characteristics of providing strong coherent light at the micro-nano scale. With the development of miniaturized integrated photonics circuits, micro-nano lasers are required to have higher information density and bandwidth. Therefore, it is hoped that these lasers have the characteristics of switchable output wavelength and high spectral purity at the same time, that is, wavelength-switchable single-mode lasers . Organic photofunctional materials have rich energy level structures and excited state processes, which provide an ideal material platform for the construction of multi-wavelength switchable lasers. However, due to the relatively limited band gap width of a single gain medium, the tuning range of a wavelength-switchable laser based on a single gain medium is very limited.

The resonance energy transfer process (FRET) can realize the energy transfer from the donor molecule to the acceptor molecule, which effectively expands the tuning range of the laser output wavelength, so it is expected to realize a broad-spectrum switchable laser. However, the efficiency of FRET is usually controlled by the stoichiometric ratio of the donor and the acceptor. Once the concentration of the laser dye in the system is fixed, the wavelength of the output laser is often constant. Applications in switchable lasers. Therefore, the development of a FRET laser system with dynamically tunable stoichiometry of the acceptor will be very beneficial to the construction of a broad-spectrum switchable single-mode micro-nano laser.

SUMMARY OF THE INVENTION

In order to improve the deficiencies of the prior art, the present invention adopts the following technical solutions:

A light-controlled broad-spectrum switchable single-mode laser, the light-controlled process is realized by photochromic molecules with controllable light isomerization, and the isomerization process in the photochromic gain material can realize the energy transfer acceptor. The concentration adjustment is used to dynamically control the change of the gain interval of the microcavity; the single-mode laser is realized by a coupled double-disk structure prepared by controllable processing.

The present invention also provides a method for preparing the above-mentioned optically controlled broad-spectrum switchable single-mode laser, the method comprising the following steps:

1) The polymer LOR glue is used as the pillar part of the micro-cavity structure, and is spin-coated on the conductive substrate to form a film, heated and dried, and the solvent is removed to obtain the LOR glue film sample;

2) Uniformly disperse the acceptor gain medium in the chlorobenzene solution of the polymer photoresist, spin-coat the LOR film sample obtained in step 1) to form a film, heat and dry it, remove the solvent, and obtain a coating dye blend. Heteropolymer photoresist substrates;

3) According to the pre-designed pattern, the structure of the coupled microcavity is prepared on the polymer film sample prepared in step 2) by using the electron beam etching (EBL) method;

4) developing and fixing the sample obtained in step 3) with a developer to obtain a polymer-coupled microcavity structure;

5) The sample obtained in step 4) is developed and fixed with LOR developing solution, and an undercut structure is formed at the lower part of the polymer microdisk to obtain an organic micro-nano laser with a supporting structure, which is the optically controlled broad-spectrum switchable monolith. mode laser.

The present invention also provides a method for adjusting the above-mentioned optically controlled broad-spectrum switchable single-mode laser. Using the above-mentioned preparation method of an organic micro-nano device, a single circular organic micro-nano laser with a supporting structure is prepared, and photochromic can be controlled by ultraviolet irradiation. The photoisomerization process of molecules can effectively adjust the concentration of the receptors in the microcavity, thereby regulating the energy transfer process between the receptors, and then realizing a broad-spectrum switchable micro-nano laser.

Preferably, the above-mentioned adjustment method of the optically controlled broad-spectrum switchable laser includes the following steps:

1) The coupled microdisk is used as an optical gain unit and a laser filter unit at the same time, no ultraviolet irradiation is performed on the microdisk, and the two microcavities simultaneously realize the output of the donor single-mode laser;

2) On the basis of step 1), ultraviolet irradiation is performed on one of the microdisks of the coupling structure, and the two microdisks with different luminescence colors are respectively used as a gain unit and a filter unit, which can simultaneously realize the single-mode laser output of the donor and the acceptor;

3) On the basis of step 2), ultraviolet irradiation is performed on the two microdisks of the coupling structure, and the two microcavities simultaneously realize the output of the acceptor single-mode laser light.

The invention also provides the application of the above-mentioned optically controlled broad-spectrum switchable single-mode laser in the fields of biochemical sensing, laser display or integrated photonics circuit, preferably for high-density photonics integration.

Beneficial effects of the present invention:

The inventors have surprisingly found that organic materials have excellent doping flexibility and can be doped with functional molecules such as laser dyes to realize the preparation of active luminescent optical functional devices in the visible spectrum range, including but not Limited to micro-nano lasers. Organic materials also have good mechanical flexibility and processability, and can be fabricated into high-quality micro-nano optical microcavities; the micro-nano optical structures can perform good confinement and modulation of photons.

1. The present invention provides a light-controlled broad-spectrum switchable single-mode laser and a preparation method thereof. The preparation method is to process a polymer film doped with an acceptor dye into a support structure by using an electron beam processing method. The organic micro-nano coupled resonant cavity, the acceptor dye is a photochromic molecule, and the isomerization process in the photochromic gain material can realize the concentration adjustment of the energy transfer acceptor, which is used to dynamically control the emission wavelength of the microcavity. Variety. The coupled resonator can provide optical feedback and mode selection for the stimulated radiation of the gain medium, so as to realize the output of single-mode laser light.

2. The present invention provides an adjustment method for an optically controlled broad-spectrum switchable single-mode laser, and the optically controlled process can realize the adjustment of the gain interval of a single microcavity in the coupling structure. The energy transfer process in the two microdisks in the coupled structure can be regulated respectively, and the controllable regulation of the broad-spectrum switchable single-mode laser can be realized.

The dynamic energy transfer process is achieved by a photochromic molecule with a photoisomerization process as an acceptor; the photoisomerization process is caused by the light-induced structural transformation of the photochromic molecule, one of which is isomerized. The body acts as an energy receptor, and the change of the concentration of the photo-controlled receptor can effectively regulate the energy transfer process between the receptors and realize a wide-spectrum tunable micro-nano laser. The single-mode laser is realized by a coupled resonator, which can provide optical feedback and mode selection for the stimulated radiation of the gain medium, so as to realize the output of the single-mode laser; The energy transfer process in the two resonators is controlled separately, which not only broadens the adjustment range of the laser wavelength, but also realizes the controllable switching of dual wavelengths in the same system; the broad-spectrum tunable single-mode laser can be used for high Density Geophotonics Integration.

Description of drawings

FIG. 1 is a schematic diagram of the preparation process of the organic micro-nano resonant cavity with a support structure of Example 1. FIG.

FIG. 2 is the front and side SEM images of the organic micro-nano resonator with the support structure of Example 1. FIG.

FIG. 3 is a schematic diagram of dynamic energy transfer achieved by the controllable photoisomerization acceptor and OPV donor in Example 1. FIG.

4 is the photoluminescence spectrum of the organic micro-nano resonator doped with the acceptor of Example 1 as a function of femtosecond pump light power.

FIG. 5 is the photoluminescence spectrum of the organic micro-nano resonator doped with the acceptor of Example 1 after the ultraviolet exposure with the change of the power of the femtosecond pump light.

FIG. 6 is the regulation of the two-color laser in the organic micro-nano resonator doped with the acceptor of Example 1. FIG.

FIG. 7 is a fluorescence micrograph of a double-disk coupled microcavity obtained by coupling two organic micro-nano lasers with supporting structures of different sizes to each other under different ultraviolet exposure times in Example 4. FIG.

FIG. 8 is a graph of the laser performance test of the double-disk coupling structure doped with the acceptor dye prepared in Example 4. FIG.

Detailed ways

As mentioned above, the present invention provides an optically controlled broad-spectrum switchable single-mode laser.

In a preferred embodiment of the present invention, the laser has a micro-nano structure and is doped with laser dye, which can be used as a laser light source.

In a preferred embodiment of the present invention, the organic micro-nano single-mode laser is an organic micro-nano resonator with a support structure, and the support structure near one end of the substrate can well separate the organic micro-nano resonator from the substrate , effectively reducing the optical field loss caused by the substrate, which will greatly improve the quality factor of the optical organic micro-nano laser, which is beneficial to the realization of the low-threshold micro-nano laser.

In a preferred embodiment of the present invention, the material of the organic micro-nano single-mode laser with a supporting structure is a polymer that can undergo molecular chain scission under EBL conditions. The material is polymethyl methacrylate (PMMA) photoresist and the like.

In a preferred embodiment of the present invention, the organic micro-nano single-mode laser with a supporting structure includes a gain medium for the acceptor, and the concentration ratio of the gain medium for the acceptor is 10-100 wt %, for example, 50wt%; the acceptor gain medium is selected from photochromic molecules with photoisomerization, and the photochromic molecules are selected from laser dyes with four-level structure, such as spiropyran photochromic molecules ; For example, 1',3'-dihydro-1',3',3'-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2' shown in formula (1) -(2H)-indole] (BIPS), formula (1) is ring-opened by light to obtain formula (2), formula (2) is a gain molecule (BIPS-MC) with a four-level structure; the donor gain The medium is selected from a green laser dye that matches the absorption and emission of the acceptor gain molecule, such as 1,4-bis(R-cyano-4-diphenylaminostyryl)-2,5-diphenylbenzene(OPV) shown in formula (3).

Exemplarily, the diameter of the organic micro-nano laser is 6-20 μm (for example, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 20 μm), and the thickness (or defined as height) is 1-2 μm (for example, 1 μm, 1.2 μm, 1.5 μm, 1.8 μm, 2 μm), preferably, the organic micro-nano laser has a diameter of 15 μm and a thickness of 1.5 μm.

In a preferred embodiment of the present invention, the shape of the support structure is an isotropic cylindrical structure. If the organic micro-nano laser is in contact with the substrate, the light field will leak and the laser threshold will increase. The height of the support structure is 1-5 μm (for example, 1 μm, 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, 5 μm), preferably, the height of the supporting structure is 2 μm.

In a preferred embodiment of the present invention, the organic micro-nano single-mode laser is a double-disk coupled micro-nano single-mode laser obtained by coupling two organic micro-nano lasers with supporting structures of different sizes to each other. Exemplarily, the diameter of the double-disk coupled micro-nano single-mode laser is 6-20 μm (for example, d ₁ /d ₂ is 8/10 μm, 8/12 μm, 10/12 μm, 12/14 μm, 12/16 μm), preferably The diameter of the organic micro-nano laser is 12/14 μm.

In a preferred embodiment of the present invention, the organic micro-nano laser has a smooth surface, which can effectively confine photons, with small transmission loss and strong interaction between light and matter.

In a preferred embodiment of the present invention, the dielectric material for constructing a light-controlled broad-spectrum switchable laser has good photoresponsivity, and under the irradiation of ultraviolet light and visible light, it is helpful to realize light-controlled micro-nano Fabrication of laser devices.

As mentioned above, the present invention also provides a method for preparing the above-mentioned optically controlled broad-spectrum switchable single-mode laser, the method comprising the following steps:

1) The polymer LOR glue is used as the pillar part of the micro-cavity structure, and is spin-coated on the conductive substrate to form a film, heated and dried, and the solvent is removed to obtain the LOR glue film sample;

2) uniformly dispersing the acceptor gain medium in the organic solvent of the polymer PMMA, spin-coating to form a film on the substrate obtained in step 1), heating and drying, and removing the solvent to obtain a dye-doped PMMA substrate;

3) According to the pre-designed pattern, using the electron beam processing method, prepare the structure of the coupled microcavity on the PMMA film sample prepared in step 2);

4) developing and fixing the sample obtained in step 3) with a PMMA developer to obtain a PMMA coupled microcavity structure;

5) The sample obtained in step 4) is developed and fixed with LOR developing solution, and an undercut structure is formed at the lower part of the PMMA microdisk to obtain an organic micro-nano single-mode laser with a supporting structure, that is, the light-controlled broad-spectrum switchable single-mode laser is obtained. mode laser.

In a preferred embodiment of the present invention, in step (1), the polymer LOR layer is preferably LOR5A, which is easy to form a film and will not change under etching conditions (such as electron beam bombardment). , a developer that will not dissolve in PMMA, so that an isotropic undercut structure can be achieved.

In a preferred embodiment of the present invention, in step (1), the thickness of the polymer LOR layer is 1-5 μm. Preferably, the height of the LOR layer is 2 μm.

In a preferred embodiment of the present invention, in step (1), the conductive substrate may be ITO, silicon wafer, silver substrate, or the like. Preferably, the conductive substrate is a silicon wafer.

In a preferred embodiment of the present invention, in step (1), the heating temperature is 170-190° C., preferably 180° C., and the heating time is within 5-20 minutes, preferably 10 minutes.

In a preferred embodiment of the present invention, in step (2), the doping mass ratio of the acceptor gain medium in the polymer PMMA (polymethyl methacrylate) is 10-100 wt %, for example, 50wt%, the doping of the acceptor gain medium can not only provide sufficient optical gain, but also provide a variable unit of optical modulation.

In a preferred embodiment of the present invention, in step (2), the polymer is preferably polymethyl methacrylate (PMMA), which is easy to form a film and can be easily etched under etching conditions (such as electron beam Under bombardment), the covalent bond is broken, and the solubility in the same solvent changes, thereby realizing patterning.

In a preferred embodiment of the present invention, in step (2), the organic solvent may be one of dimethylformamide (DMF), toluene, chlorobenzene, chloroform, dichloromethane, chloroform, etc. one or more. Preferably, the organic solvent is chlorobenzene.

In a preferred embodiment of the present invention, in step (2), the mass percentage of the polymer in the organic solvent is 8%-16%, for example, 10%.

In a preferred embodiment of the present invention, in step (2), the thickness of the polymer PMMA layer is 1-2 microns.

In a preferred embodiment of the present invention, in step (2), the heating temperature is 170-190° C., preferably 180° C., and the heating time is within 1-5 minutes, preferably 2 minutes.

In a preferred embodiment of the present invention, in step (3), the voltage of the electron beam is 25-30 kV, preferably 30.0 kV, and the electron beam spot of the electron beam is 3.3-3.5, preferably 3.50.

In a preferred embodiment of the present invention, in step (4), the developer of the polymer PMMA is a mixed solvent of MIBK:IPA=1:3, and the fixer is an IPA solvent.

In a preferred embodiment of the present invention, in step (4), the developing time is 20-50 seconds, preferably 30 seconds, and the fixing time is 20-50 seconds, preferably 30 seconds.

In a preferred embodiment of the present invention, in step (5), the developer of the polymer LOR is 101 developer.

In a preferred embodiment of the present invention, in step (5), the developing time is 3-7 minutes, preferably 5 minutes, and the fixing time is 20-50 seconds, preferably 30 seconds.

The present invention provides a method for adjusting the above-mentioned optically controlled broad-spectrum switchable single-mode laser. Using the above-mentioned preparation method for a micro-nano device, a coupled micro-disk structure with a support structure is prepared. By separately controlling the photoisomerization process of photochromic molecules in the two polymer microdisks, the concentration of the receptors can be effectively adjusted, thereby controlling the energy transfer between the receptors, and a broad-spectrum switchable single-mode laser can be realized .

The present invention will be further described below in conjunction with specific embodiments. It should be understood that these examples are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the contents described in the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the limited scope of the present invention.

Unless otherwise stated, the starting materials and reagents used in the following examples are commercially available or can be prepared by known methods.

Example 1

The LOR5A was used as the pillar part of the structure, and the LOR polymer film was obtained by homogenizing on the silicon substrate with a homogenizer, and the residual solvent was removed by baking at 180 °C for 10 minutes. After that, a PMMA polymer chlorobenzene solution with a mass concentration percentage of 10% was prepared, and BIPS and OPV dyes with a mass concentration ratio of 50% were doped. The PMMA polymer film was obtained by homogenizing the LOR polymer film with a glue dispenser, and the temperature was 180°C. Bake for two minutes to remove residual dilution solvent. Then, the polymer film was exposed to electron beam according to the designed microdisk pattern, the voltage was 30.0kV, and the electron beam spot was 3.50. After exposure, the PMMA and LOR were developed respectively to obtain an organic micro-nano laser with a supporting structure.

FIG. 1 is a flow chart of the preparation process of the organic microdisk of the support structure of Example 1. FIG. It can be seen from FIG. 1 that a plurality of independent organic micro-nano lasers with supporting structures are prepared by EBL, and the morphology of the organic micro-nano lasers is a micro-disk structure.

A and B in FIG. 2 are the front and side SEM images of a single organic micro-nano laser. The scanning electron microscope photos A and B correspond to a micro-nano laser with a diameter of d=12 μm, and the surface is smooth and defect-free. It can be seen from FIG. 2 that the cavity for optical feedback in the organic micro-nano laser is separated from the substrate, and the diameter and thickness of the disk cavity are highly controllable, which is basically consistent with the designed size. The A and B scales in Figure 2 are 5 μm.

Example 2

Analysis and Characterization of Dynamic Energy Transfer Processes

Specifically, as shown in Figure 3 and Figure 4, Figure 3 shows the energy transfer process between the donor and the acceptor. Under the irradiation of ultraviolet light and visible light, the C-O bond in the BIPS molecule is broken and restored, so that the photochromic molecule can be colorless. A reversible transition occurs between the spiropyran (BIPS) and the red merocyanine (BIPS-MC). The absorption spectrum of BIPS-MC and the emission spectrum of OPV have a large spectral overlap, which is favorable for resonance energy transfer between the two molecules. FIG. 4 shows the change of the fluorescence spectrum of the PMMA film doped with the acceptor with the change of the UV exposure time. With the increase of UV exposure time, BIPS gradually isomerized into BIPS-MC, the concentration of BIPS-MC in the PMMA film increased, the energy transfer efficiency between OPV and BIPS-MC increased, and the film luminescence gradually changed from the given luminescence at 550 nm. It emits light for the acceptor at 690 nm. The above-mentioned optically controlled energy transfer process provides a way to dynamically adjust the dual-wavelength gain, and provides a material basis for the realization of a wide-spectrum tunable laser.

Example 3

Analysis and Characterization of Broad Spectrum Tunable Lasers

FIG. 5 and FIG. 6 are the response performance test diagrams of the organic micro-nano laser with a diameter of 16 μm, a thickness of 1.5 μm and a support height of 2 μm doped with BIPS prepared in Preparation Example 1. In Fig. 5, A is the photoluminescence spectrum of the above-mentioned organic microdisc with the pump power after irradiation with ultraviolet light; in Fig. 5, B is the relationship between the laser peak intensity of the above-mentioned organic microdisc and the pump power, indicating that in our preparation Low-threshold lasing is achieved within the organic microdisks. A in Figure 6 is the resonant energy transfer process of the above-mentioned organic microdisc's laser light changing with ultraviolet light. Before ultraviolet light irradiation, there is no energy acceptor, and the stimulated emission of the OPV donor is realized; during ultraviolet light irradiation, the energy transfer acceptor The concentration gradually increases, the energy transfer process is enhanced, and the stimulated emission of the acceptor gain medium is realized. B in Fig. 6 is the fluorescence decay curve of the above-mentioned organic microdisk at 550 nm under different UV illumination times; C in Fig. 6 is the fluorescence lifetime obtained by fitting the decay curve under different UV illumination times and calculated for the acceptor The energy transfer efficiency between OPV and BIPS-MC, the lifetime and the change of energy transfer efficiency in the figure also illustrate the resonance energy transfer between OPV and BIPS-MC. D in Figure 6 is the tunable two-color laser spectrum of the above organic microdisk. It can be seen that the laser spectrum at 560 nm gradually weakens with the increase of UV irradiation time; on the contrary, the laser at 700 nm gradually increases. The above results prove that the photochromic molecule BIPS has a good photoresponsivity. Using BIPS-MC as the energy acceptor can control the energy transfer efficiency through illumination, and can realize the dynamic adjustment of multi-wavelength lasers.

Example 4

Other steps are the same as in Example 1, the difference is only that when the film sample is exposed to electron beam, the film is controllably exposed according to the designed organic micro-nano laser model, that is, the data patterns imported during the exposure process are two different. A double-disk-coupled laser with a supporting structure is obtained by coupling the microdisks of different sizes to each other.

In Example 4, a double-disk coupling structure obtained by coupling two organic micro-nano lasers with supporting structures of different sizes to each other was prepared. Specifically, as shown in FIG. 7 , FIG. 7 is the fluorescence micrographs of the double-disk coupled microcavity obtained by coupling two organic micro-nano lasers with supporting structures of different sizes to each other under different ultraviolet irradiation times (A , B, C). The scale of the graph is 20 μm. It can be seen from Fig. 7 that the above-mentioned two organic double-disk coupling microcavities with different sizes with supporting structures have different sizes, with diameters of 12 μm and 14 μm, respectively, and the coupling spacing between the double disks is 0.5 μm, and has a very large size. Good light responsiveness.

FIG. 8 is a graph of the laser performance test of the double-disk coupling structure doped with the acceptor dye prepared in Example 4. FIG. Among them, A in Figure 8 is a stable single-mode laser obtained by the double-disk coupled microdisk structure. It can be seen from the two single-disk lasers with diameters of 12 μm and 14 μm obtained in Example 1 that there is a single-mode laser in the gain interval. The modes are selectively amplified to obtain coupled microdisk single-mode laser output. B in Figure 8 is the relationship between the laser peak intensity of the above-mentioned dual-disk coupled micro-nano laser with respect to the pump power, and single-mode laser can be realized within a larger pump power range. C in FIG. 8 is the variation of the single-mode laser light obtained by the above-mentioned double-disk coupling structure based on the dynamic energy transfer process under different ultraviolet light irradiation conditions. The coupled microdisk is used as both the optical gain unit and the laser filter unit, and the microdisk is not irradiated with ultraviolet light, and the two microcavities simultaneously realize the output of the donor single-mode laser (550nm); the UV irradiation is performed on one of the microdisks in the coupling structure, and the two are different. The microdisks with luminescent colors are used as gain unit and filter unit respectively, which can realize single-mode laser output (550nm and 700nm) of the donor and acceptor at the same time; UV irradiation is applied to the two microdisks of the coupling structure, and the two microcavities simultaneously realize the receiving The exit of bulk single-mode laser light (700 nm). The diameters of the two microdisks in the dual-disk coupling micro-nano laser are 12 μm and 14 μm, respectively, and the supporting height is 2 μm and the thickness is 1.5 μm. The scale bar in Figure 8 is 10 μm.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A light-operated wide-spectrum switchable single-mode laser is characterized in that the light-operated process is realized by taking photochromic molecules which can be controlled by illumination as energy receptors;

the light-operated wide-spectrum switchable single-mode laser has an organic micro-nano structure, is doped with controllable donor and acceptor laser dyes, and can be used as a laser light source and a spectrum filtering unit at the same time.

2. The optically controlled broad-spectrum switchable single-mode laser according to claim 1, wherein the organic micro-nano laser is an organic micro-nano resonant cavity with a support structure.

Preferably, the organic micro-nano resonant cavity with the support structure is made of polymethyl methacrylate photoresist.

3. The optically controlled broad-spectrum switchable single-mode laser according to claim 2, wherein preferably, the organic micro-nano laser with the supporting structure comprises a donor gain medium and a acceptor gain medium, and the concentration ratio of the donor gain medium to the acceptor gain medium is 10-100 wt%; the receptor gain medium is selected from photochromic molecules with photoisomerization, and the photochromic molecules are selected from spiropyran photochromic molecules; for example, 1 ', 3' -dihydro-1 ', 3', 3 '-trimethyl-6-nitro spiro [ 2H-1-benzopyran-2, 2' - (2H) -indole ] represented by the formula (1) or the formula (2); the donor gain medium is selected from green laser dyes matched with absorption and emission of acceptor gain molecules, such as 1,4-bis (R-cyano-4-diphenylaminostyryl) -2, 5-diphenylbezene shown in formula (3);

4. the optically controlled wide-spectrum switchable single-mode laser according to claim 2 or 3, wherein the organic micro-nano laser is a cylindrical structure, a microdisk structure, a cubic structure, a cuboid structure, a sphere structure, a polygonal prism structure, a hemisphere structure or a micro-ring structure.

Preferably, the diameter of the organic micro-nano laser is 6-20 μm, and the thickness of the organic micro-nano laser is 1-2 μm, and preferably, the diameter of the organic micro-nano laser is 12 μm, and the thickness of the organic micro-nano laser is 1.5 μm.

Preferably, the support structure is in the shape of an isotropic cylindrical structure. Preferably, the height of the support structure is 1-5 μm, preferably the height of the support structure is 2 μm.

5. The optically controlled wide-spectrum switchable single-mode laser according to any one of claims 2 to 4, wherein the organic micro-nano laser is a double-disk coupled micro-nano laser obtained by coupling two organic micro-nano resonant cavities with different sizes and supporting structures.

Preferably, the diameter of the double-disc coupling micro-nano laser is 6-20 μm, and preferably, the diameters of the organic micro-nano laser are 12 μm and 14 μm respectively.

6. A method of fabricating an optically controlled broad-spectrum switchable single mode laser as claimed in any one of claims 1 to 5, comprising the steps of:

1) the polymer LOR glue is used as a support part of a microcavity structure, spin-coated on a conductive substrate to form a film, heated and dried, and the solvent is removed to obtain an LOR glue film sample;

2) uniformly dispersing donor and acceptor molecules in an organic solvent of a polymer, spin-coating the LOR glue film sample obtained in the step 1) to form a film, heating and drying, and removing the solvent to obtain a polymer substrate doped with a coating dye;

3) preparing a coupling microcavity structure on the polymer film sample prepared in the step 2) by adopting a micro-nano processing method according to a pre-designed pattern;

4) developing and fixing the sample obtained in the step 3) by using a polymer developing solution to obtain a polymer coupling microcavity structure;

5) developing and fixing the sample obtained in the step 4) by using an LOR developing solution, forming an undercut structure at the lower part of the polymer microdisk, and obtaining the organic micro-nano single-mode laser with a supporting structure, namely the light-operated wide-spectrum switchable single-mode laser.

7. The method for preparing the optically controlled wide-spectrum switchable single-mode laser according to claim 6, wherein the micro-nano processing method is femtosecond laser direct writing or electron beam etching, preferably electron beam etching.

8. The method of claim 6 or 7, wherein in step (1), said polymer LOR layer is LOR 5A.

Preferably, in step (1), the polymer LOR layer has a thickness of 1-5 μm. Preferably, the LOR layer has a height of 2 μm.

Preferably, in step (1), the conductive substrate is a silicon wafer.

Preferably, in step (1), the heating temperature is 170-190 ℃, preferably 180 ℃, and the heating time is within 5-20 minutes, preferably 10 minutes.

Preferably, in step (2), the polymer is polymethyl methacrylate (PMMA).

Preferably, in step (2), the organic solvent is chlorobenzene.

Preferably, in the step (2), the mass percentage of the polymer in the organic solvent is 8-16%.

Preferably, in step (2), the polymer layer has a thickness of 1 to 2 microns.

Preferably, in step (2), the heating temperature is 170-190 ℃, preferably 180 ℃, and the heating time is within 1-5 minutes, preferably 2 minutes.

Preferably, in step (2), the acceptor molecule is a photochromic molecular spiropyran having photoisomerization.

Preferably, in step (2), the donor molecule is a laser dye that matches the absorption emission of the acceptor gain molecule.

Preferably, in step (2), the doping ratio of the donor to the polymer PMMA is 10-100 wt%.

Preferably, in step (3), the voltage of the electron beam is 25 to 30kV, preferably 30.0kV, and the electron beam spot of the electron beam is 3.3 to 3.5, preferably 3.50.

Preferably, in the step (4), the developer of the polymer PMMA is MIBK: IPA is a 1:3 mixed solvent, and the fixing solution is an IPA solvent.

Preferably, in step (4), the developing time is 20 to 50 seconds, preferably 30 seconds, and the fixing time is 20 to 50 seconds, preferably 30 seconds.

Preferably, in step (5), the developing solution of the polymer LOR is 101 developer.

Preferably, in step (5), the developing time is 3 to 7 minutes, preferably 5 minutes, and the fixing time is 20 to 50 seconds, preferably 30 seconds.

9. The method for adjusting an optically controlled wide-spectrum switchable single-mode laser as claimed in any one of claims 1 to 5, wherein the photoisomerization process of photochromic molecules can be controlled by ultraviolet irradiation, and the concentration of the receptors in the microcavity can be effectively adjusted, so as to adjust the energy transfer process between the receptors, and further realize the wide-spectrum switchable micro-nano laser.

Preferably, the adjusting mode is optically controlled to adjust the energy transfer process in the coupled microdisk.

10. Use of the optically controlled broad-spectrum switchable single-mode laser according to any of claims 1 to 5 in the field of biochemical sensing, laser display or integrated photonics circuits, preferably for high-density photonics integration.

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