阅读说明：本技术 深紫外微腔激光器及其制备方法 (Deep ultraviolet micro-cavity laser and preparation method thereof ) 是由 王婷 余兆丰 于 2019-09-03 设计创作，主要内容包括：本发明属于激光器技术领域,尤其涉及一种深紫外微腔激光器,包括：微晶玻璃载体和生长在所述微晶玻璃载体内部的稀土纳米晶体,所述稀土纳米晶体包括纳米晶载体和稀土离子,所述稀土离子包括：Ho~(3+)、Tm~(3+)中的至少一种,以及Yb~(3+)。本发明提供的深紫外微腔激光器,以微晶玻璃作为微腔激光器的基体,微晶玻璃具有优异的热稳定性和化学稳定性,为直接均匀生长在微晶玻璃载体内部的稀土纳米晶体提供基体,使深紫外微腔激光器具有优异的热稳定性和化学稳定性,不但适用于高温激发提高了微腔激光器耐激发性和使用寿命,而且适用于高密度激发提高了微腔激光器的深紫外发射效率。(The invention belongs to the technical field of lasers, and particularly relates to a deep ultraviolet micro-cavity laser, which comprises: the glass-ceramic carrier and the rare earth nanocrystals growing inside the glass-ceramic carrier, wherein the rare earth nanocrystals comprise a nanocrystal carrier and rare earth ions, and the rare earth ions comprise: ho 3+ 、Tm 3+ And Yb, and 3+ . According to the deep ultraviolet micro-cavity laser, the microcrystalline glass is used as the substrate of the micro-cavity laser, the microcrystalline glass has excellent thermal stability and chemical stability, the substrate is provided for the rare earth nanocrystals directly and uniformly growing in the microcrystalline glass carrier, the deep ultraviolet micro-cavity laser has excellent thermal stability and chemical stability, and the deep ultraviolet micro-cavity laser is suitable for high-temperature excitation, improves the excitation resistance and service life of the micro-cavity laser, is suitable for high-density excitation and improves the deep ultraviolet emission efficiency of the micro-cavity laser.)

1. A deep ultraviolet micro-cavity laser, comprising: the glass-ceramic carrier and the rare earth nanocrystals growing inside the glass-ceramic carrier, wherein the rare earth nanocrystals comprise a nanocrystal carrier and rare earth ions, and the rare earth ions comprise: ho³⁺、Tm³⁺And Yb, and³⁺。

2. the deep ultraviolet microcavity laser of claim 1, wherein: the rare earth ions further comprise Gd³⁺(ii) a And/or the presence of a gas in the gas,

the nanocrystalline carrier is selected from: NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄At least one of; and/or the presence of a gas in the gas,

the microcrystalline glass carrier is selected from: 45SiO 2₂-15Al₂O₃-12Na₂O、45SiO₂-15Al₂O₃-16NaF、30SiO₂-20Al₂O₃-10Bi₂O₃、45SiO₂-15Al₂O₃-12Na₂CO₃Any one of them.

3. The deep ultraviolet micro-cavity laser of claim 2, wherein in the deep ultraviolet micro-cavity laser, the molar ratio of the microcrystalline glass carrier to the rare earth nanocrystals is (1-2): (1-5); and/or the presence of a gas in the gas,

the Yb in the cation of the rare earth nanocrystal³⁺The molar percentage content of the compound is 10 to 80 percent; the Ho³⁺And Tm³⁺The total mole percentage content of the active carbon is 0.1 to 15 percent; the Gd³⁺The molar percentage of the component (a) is 0-5%.

4. The deep ultraviolet microcavity laser as claimed in any one of claims 1 to 3, wherein the deep ultraviolet microcavity laser is a cylinder with a length of 0.5-5 μm and a diameter of 20-500 nm.

5. The deep ultraviolet micro-cavity laser of claim 4, wherein first Bragg reflection layers with reflectivity of 75% -95% for 200-300 nm waveband are deposited at two ends of the deep ultraviolet micro-cavity laser.

6. The deep ultraviolet microcavity laser as claimed in claim 5, wherein a second bragg reflector having a reflectivity of 100% in an undesired band is further disposed on a surface of the first bragg reflector facing away from the deep ultraviolet microcavity laser cavity.

7. A preparation method of a deep ultraviolet micro-cavity laser is characterized by comprising the following steps:

obtaining a microcrystalline glass carrier material, a nanocrystalline carrier material and a rare earth ion precursor, mixing the microcrystalline glass carrier material, the nanocrystalline carrier material and the rare earth ion precursor, and then carrying out high-temperature calcination treatment to obtain amorphous glass;

after the amorphous glass is drawn, high-temperature annealing treatment is carried out, and the glass optical fiber is obtained after cooling;

and after the glass optical fiber is cut, a Bragg reflection layer is deposited on the cutting surface of the glass optical fiber, and the deep ultraviolet micro-cavity laser is obtained.

8. The method for preparing the deep ultraviolet micro-cavity laser as claimed in claim 7, wherein the conditions of the high temperature calcination process include: calcining for 1-3 hours in the atmosphere at the temperature of 1300-1650 ℃; and/or the presence of a gas in the gas,

after the amorphous glass is drawn, the high-temperature annealing treatment comprises the following steps: after the amorphous glass is subjected to melt wire drawing, annealing for 1-3 hours at the temperature of 300-700 ℃, and separating out rare earth nanocrystals; and/or the presence of a gas in the gas,

the step of depositing a Bragg reflection layer on the cutting surface of the glass optical fiber after the glass optical fiber is cut comprises the following steps: and cutting the glass optical fiber into a cylindrical shape, and depositing first Bragg reflecting layers with the reflectivity of 75% -95% for 200-300 nanometer wave bands on cutting surfaces at two ends of the glass optical fiber.

9. The method of claim 8, wherein the step of depositing a bragg reflector on the cut surface of the glass optical fiber further comprises: and depositing a second Bragg reflection layer with the reflectivity of 100% for the undesired waveband on the surface of the first Bragg reflection layer far away from the glass optical fiber.

10. The method for manufacturing the deep ultraviolet micro-cavity laser as claimed in any one of claims 7 to 9, wherein the diameter of the deep ultraviolet micro-cavity laser is 20 to 500 nm, and the length is 0.5 to 5 mm.

Technical Field

The invention belongs to the technical field of lasers, and particularly relates to a deep ultraviolet micro-cavity laser and a preparation method thereof.

Background

In recent years, compared with incoherent light sources such as synchrotron radiation and gas discharge, the low-cost deep ultraviolet micro-cavity laser (< 300nm) has the characteristics of high photon energy, high spectral resolution, strong photon flow and high density, and can be operated in multiple operation modes such as low repetition frequency, high repetition frequency and nanosecond, and has wide application prospects in the fields of air, water and food sterilization and purification, micro-fine material processing, photoetching, photo-printing, high-resolution spectroscopy, microelectronics, photobiology, ultrahigh-density optical drive, ultraviolet curing, medical treatment, scientific research and the like. The size of the focused spot of the deep ultraviolet laser light source can be reduced to the range of tens of nanometers through selection of the deep ultraviolet laser light source. This not only facilitates improved optical data storage precision, but also facilitates implementation of a non-contact lithography system. In addition, the transmission distance of the stronger ultraviolet signal in the earth atmosphere is only several kilometers, and the stronger ultraviolet signal can avoid signal interception and interference of external signals in short-distance information transmission, so that the portable deep ultraviolet laser can be an ideal carrier for short-distance wireless communication, can be particularly used for ultraviolet communication, high-energy laser weapons, laser radars, high-precision laser ranging and the like in military affairs, greatly improves the military strength of China, and has very important significance.

At present, due to the extremely low up-conversion luminous efficiency and poor thermal stability of the laser, the deep ultraviolet excitation emission of less than 300nm through near infrared laser excitation is difficult to realize.

Disclosure of Invention

The invention aims to provide a deep ultraviolet microcavity laser, and aims to solve the technical problems that the conversion luminescence efficiency of the existing deep ultraviolet laser is low, the thermal stability is poor, the deep ultraviolet excitation emission smaller than 300nm is difficult to realize, and the like.

The invention also aims to provide a preparation method of the deep ultraviolet micro-cavity laser.

In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows:

a deep ultraviolet micro-cavity laser, comprising: the glass-ceramic carrier and the rare earth nanocrystals growing inside the glass-ceramic carrier, wherein the rare earth nanocrystals comprise a nanocrystal carrier and rare earth ions, and the rare earth ions comprise: ho³⁺、Tm³⁺And Yb, and³⁺。

preferably, the rare earth ion further comprises Gd³⁺(ii) a And/or the presence of a gas in the gas,

the nanocrystalline carrier is selected from: NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄At least one of; and/or the presence of a gas in the gas,

the microcrystalline glass carrier is selected from: 45SiO 2₂-15Al₂O₃-12Na₂O、45SiO₂-15Al₂O₃-16NaF、30SiO₂-20Al₂O₃-10Bi₂O₃、45SiO₂-15Al₂O₃-12Na₂CO₃Any one of them.

Preferably, in the deep ultraviolet micro-cavity laser, the molar ratio of the microcrystalline glass carrier to the rare earth nanocrystal is (1-2): (1-5); and/or the presence of a gas in the gas,

the Yb in the cation of the rare earth nanocrystal³⁺The molar percentage content of the compound is 10 to 80 percent; the Ho³⁺And Tm³⁺The total mole percentage content of the active carbon is 0.1 to 15 percent; the Gd³⁺The molar percentage of the component (a) is 0-5%.

Preferably, the deep ultraviolet micro-cavity laser is cylindrical with the length of 0.5-5 microns and the diameter of 20-500 nanometers.

Preferably, the two ends of the deep ultraviolet micro-cavity laser are deposited with first Bragg reflecting layers with reflectivity of 75% -95% to 200-300 nanometer wave bands.

Preferably, a second bragg reflection layer with reflectivity of 100% for an undesired waveband is further arranged on the surface of the first bragg reflection layer, which is far away from the deep ultraviolet micro-cavity laser cavity.

Correspondingly, the preparation method of the deep ultraviolet micro-cavity laser comprises the following steps:

obtaining a microcrystalline glass carrier material, a nanocrystalline carrier material and a rare earth ion precursor, mixing the microcrystalline glass carrier material, the nanocrystalline carrier material and the rare earth ion precursor, and then carrying out high-temperature calcination treatment to obtain amorphous glass;

after the amorphous glass is drawn, high-temperature annealing treatment is carried out, and the glass optical fiber is obtained after cooling;

and after the glass optical fiber is cut, a Bragg reflection layer is deposited on the cutting surface of the glass optical fiber, and the deep ultraviolet micro-cavity laser is obtained.

Preferably, the conditions of the high-temperature calcination treatment include: calcining for 1-3 hours in the atmosphere at the temperature of 1300-1650 ℃; and/or the presence of a gas in the gas,

after the amorphous glass is drawn, the high-temperature annealing treatment comprises the following steps: after the amorphous glass is subjected to melt wire drawing, annealing for 1-3 hours at the temperature of 300-700 ℃, and separating out rare earth nanocrystals; and/or the presence of a gas in the gas,

the step of depositing a Bragg reflection layer on the cutting surface of the glass optical fiber after the glass optical fiber is cut comprises the following steps: and cutting the glass optical fiber into a cylindrical shape, and depositing first Bragg reflecting layers with the reflectivity of 75% -95% for 200-300 nanometer wave bands on cutting surfaces at two ends of the glass optical fiber.

Preferably, the step of depositing a bragg reflective layer on the cut surface of the glass optical fiber further includes: and depositing a second Bragg reflection layer with the reflectivity of 100% for the undesired waveband on the surface of the first Bragg reflection layer far away from the glass optical fiber.

Preferably, the diameter of the deep ultraviolet micro-cavity laser is 20-500 nanometers, and the length of the deep ultraviolet micro-cavity laser is 0.5-5 millimeters.

The deep ultraviolet micro-cavity laser provided by the invention comprises a microcrystalline glass carrier and rare earth nanocrystals growing inside the microcrystalline glass carrier, wherein the rare earth nanocrystals comprise a nanocrystal carrier and rare earth ions. On one hand, the microcrystalline glass is used as a substrate of the micro-cavity laser, the microcrystalline glass has excellent thermal stability and chemical stability, the substrate is provided for the rare earth nanocrystals directly and uniformly grown in the microcrystalline glass carrier, so that the deep ultraviolet micro-cavity laser has excellent thermal stability and chemical stability, the deep ultraviolet micro-cavity laser is suitable for high-temperature excitation, the excitation resistance and the service life of the micro-cavity laser are improved, the deep ultraviolet emission efficiency of the micro-cavity laser is improved, and the rare earth nanocrystals directly grow in the microcrystalline glassThe interior has good combination performance and high combination stability; in another aspect, the rare earth nanocrystals comprise a nanocrystal support and comprise Ho³⁺、Tm³⁺And Yb, and³⁺the nano-crystalline carrier can be combined with rare earth ions in a microcrystalline glass carrier to grow to form a nano-structured rare earth crystal, and a carrier matrix is provided for the luminescence of the rare earth ions; yb of³⁺The ions can absorb 980nm excitation light energy and transfer the energy to Ho³⁺And/or Tm³⁺Ions, make Ho³⁺And/or Tm³⁺Generation of energy level transition to realize deep ultraviolet laser emission, Ho³⁺And/or Tm³⁺And Yb³⁺The rare earth ions can realize up-conversion luminescence of deep ultraviolet in the rare earth nanocrystals. The deep ultraviolet micro-cavity laser provided by the invention has the advantages of good thermal stability, good chemical stability, capability of being effectively excited by near infrared 980nm and high excitation efficiency.

The invention provides a preparation method of a deep ultraviolet micro-cavity laser, which comprises the steps of mixing a microcrystalline glass carrier material, a nanocrystalline carrier material and a rare earth ion precursor, calcining the mixture at a high temperature to form amorphous glass, and melting and mixing the raw material components; then melting and drawing the amorphous glass, then carrying out high-temperature annealing treatment to separate out uniformly distributed rare earth nanocrystals from the microcrystalline glass carrier, and cooling to obtain the glass optical fiber; and cutting the glass fiber into a certain length to form an F-P resonant microcavity, and depositing a Bragg reflection layer on the cutting surface to obtain the deep ultraviolet microcavity laser. The preparation method of the deep ultraviolet microcavity laser provided by the invention takes the microcrystalline glass as a carrier material, rare earth ions directly precipitate rare earth nanocrystals in the microcrystalline glass carrier through the nanocrystalline carrier, and the rare earth nanocrystals directly grow and precipitate in the microcrystalline glass, so that the rare earth nanocrystals and the microcrystalline glass carrier have good combination stability, and the microcrystalline glass carrier material has excellent thermal stability, chemical stability, mechanical strength and the like, so that the prepared deep ultraviolet microcavity laser has good thermal-chemical stability, good excitation resistance and high excitation efficiency, and the deep ultraviolet laser emission is better realized.

Drawings

Fig. 1 is a schematic diagram of a deep ultraviolet micro-cavity laser provided by an embodiment of the present invention.

FIG. 2 is a diagram of an ultraviolet laser spectrum of a deep ultraviolet microcavity laser provided in embodiment 1 of the present invention, in which the excitation light density is 2 μmJ/cm from top to bottom in sequence²，3μmJ/cm²，4μmJ/cm²And 5. mu. mJ/cm²。

Detailed Description

In order to make the purpose, technical solution and technical effect of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention is clearly and completely described, and it is obvious that the described embodiments are a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art without any inventive step in connection with the embodiments of the present invention shall fall within the scope of protection of the present invention.

In the description of the present invention, it is to be understood that the terms "first", "second" and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

The weight of the related components mentioned in the description of the embodiments of the present invention may not only refer to the specific content of each component, but also represent the proportional relationship of the weight among the components, and therefore, the content of the related components is scaled up or down within the scope disclosed in the description of the embodiments of the present invention as long as it is in accordance with the description of the embodiments of the present invention. Specifically, the weight described in the description of the embodiment of the present invention may be a unit of mass known in the chemical industry field, such as μ g, mg, g, and kg.

The embodiment of the invention provides a deep ultraviolet micro-cavity laser, which is characterized by comprising the following components: microcrystalline glass carrier and rare earth nanocrystals growing inside the microcrystalline glass carrier, wherein the rare earth nanocrystals comprise nanocrystalline carrierAnd rare earth ions comprising: ho³⁺、Tm³⁺And Yb, and³⁺。

the deep ultraviolet micro-cavity laser provided by the embodiment of the invention comprises a microcrystalline glass carrier and rare earth nanocrystals growing inside the microcrystalline glass carrier, wherein the rare earth nanocrystals comprise a nanocrystal carrier and rare earth ions. On one hand, the microcrystalline glass is used as the substrate of the micro-cavity laser, the microcrystalline glass has excellent thermal stability and chemical stability, the substrate is provided for the rare earth nanocrystals directly and uniformly growing in the microcrystalline glass carrier, so that the deep ultraviolet micro-cavity laser has excellent thermal stability and chemical stability, the deep ultraviolet micro-cavity laser is suitable for high-temperature excitation, the excitation resistance and the service life of the micro-cavity laser are improved, the deep ultraviolet emission efficiency of the micro-cavity laser is improved, the rare earth nanocrystals directly grow in the microcrystalline glass, the bonding performance is good, and the bonding stability is high; in another aspect, the rare earth nanocrystals comprise a nanocrystal support and comprise Ho³⁺、Tm³⁺And Yb, and³⁺the nano-crystalline carrier can be combined with rare earth ions in a microcrystalline glass carrier to grow to form a nano-structured rare earth crystal, and a carrier matrix is provided for the luminescence of the rare earth ions; yb of³⁺The ions can absorb 980nm excitation light energy and transfer the energy to Ho³⁺And/or Tm³⁺Ions, make Ho³⁺And/or Tm³⁺Generation of energy level transition to realize deep ultraviolet laser emission of Yb³⁺And Ho³⁺And/or Tm³⁺The rare earth ions can realize up-conversion luminescence of deep ultraviolet in the rare earth nanocrystals. The deep ultraviolet micro-cavity laser provided by the embodiment of the invention has good thermal stability and chemical stability, can be effectively excited by near infrared 980nm, and has high excitation efficiency.

As a preferred embodiment, the rare earth ions further comprise Gd³⁺. The rare earth ions of the embodiment of the invention also comprise Gd³⁺，Gd³⁺Plays a role of a bridge of energy transfer in the emission of the rare earth ion deep ultraviolet excitation light, when Yb³⁺Ion absorbed excitation light energy transferHo³⁺And/or Tm³⁺Then, Ho³⁺And/or Tm³⁺The generated energy level transition can emit light of different wave bands, Gd³⁺Can convert Ho³⁺And/or Tm³⁺The energy of the emitted light with different wave bands, medium and long wavelength light, is transferred to the light with short wavelength, so that the deeper ultraviolet emission is realized, the rare earth ion luminescence selectivity is improved, and the deeper ultraviolet emission efficiency of the micro-cavity laser is improved.

In some embodiments, a deep ultraviolet microcavity laser includes: the glass-ceramic carrier and the rare earth nanocrystals growing inside the glass-ceramic carrier, wherein the rare earth nanocrystals comprise a nanocrystal carrier and rare earth ions, and the rare earth ions comprise: yb of³⁺、Ho³⁺And Gd³⁺. In other embodiments, a deep ultraviolet microcavity laser includes: the glass-ceramic carrier and the rare earth nanocrystals growing inside the glass-ceramic carrier, wherein the rare earth nanocrystals comprise a nanocrystal carrier and rare earth ions, and the rare earth ions comprise: yb of³⁺、Tm³⁺And Gd³⁺. In still other embodiments, a deep ultraviolet micro-cavity laser includes: the glass-ceramic carrier and the rare earth nanocrystals growing inside the glass-ceramic carrier, wherein the rare earth nanocrystals comprise a nanocrystal carrier and rare earth ions, and the rare earth ions comprise: yb of³⁺、Ho³⁺、Tm³⁺And Gd³⁺。

As a preferred embodiment, the nanocrystalline support is selected from: NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄At least one of (1). The rare earth nano crystal in the deep ultraviolet micro-cavity laser provided by the embodiment of the invention is composed of NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄The adopted nanocrystalline carrier has the characteristics of low phonon energy, high fluorescence efficiency and the like, not only can provide a carrier matrix for realizing deep ultraviolet up-conversion luminescence by exciting rare earth ions, but also can grow into crystals with a nano structure in microcrystalline glass through annealing and other processes, and crystals with a nano structure are separated outIn the process, rare earth ions and a nanocrystalline carrier material are subjected to ion replacement, so that nanocrystals containing rare earth ions are separated out from the microcrystalline glass carrier, and an environmental condition is provided for the luminescence of the rare earth ions. The nanocrystal carrier of the embodiment of the invention includes but is not limited to NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄The material can also be other nanocrystalline carriers as long as a carrier matrix is provided for the excitation of rare earth ions to realize deep ultraviolet up-conversion luminescence, and crystals with a nanostructure can be grown in the microcrystalline glass through annealing and other processes.

As a preferred embodiment, the microcrystalline glass support is selected from the group consisting of: 45SiO 2₂-15Al₂O₃-12Na₂O、45SiO₂-15Al₂O₃-16NaF、30SiO₂-20Al₂O₃-10Bi₂O₃、45SiO₂-15Al₂O₃-12Na₂CO₃Any one of them. According to the deep ultraviolet micro-cavity laser, the microcrystalline glass is used as a carrier material, the rare earth nanocrystals directly grow in the microcrystalline glass, the bonding effect is good, and the stability is high. Moreover, the microcrystalline glass has the excellent characteristics of high mechanical strength, excellent insulating property, low dielectric loss, stable dielectric constant, adjustable thermal expansion coefficient in a large range, chemical corrosion resistance, wear resistance, good thermal stability, high use temperature and the like, so that the microcrystalline glass with the excellent characteristics is used as a carrier material to improve the tolerance of the deep ultraviolet micro-cavity laser, such as the thermal stability, the chemical stability and the like, thereby improving the deep ultraviolet laser emission stability and the service life of the micro-cavity laser. Examples of microcrystalline glass supports include, but are not limited to, 45SiO₂-15Al₂O₃-12Na₂O、45SiO₂-15Al₂O₃-16NaF、30SiO₂-20Al₂O₃-10Bi₂O₃、45SiO₂-15Al₂O₃-12Na₂CO₃Any of them, in some embodiments, other microcrystalline glass can be used as the carrier, as long as the heat of the deep ultraviolet microcavity laser of the present invention can be increasedStability, chemical stability and other tolerance, and can improve the deep ultraviolet laser emission stability and prolong the service life of the micro-cavity laser.

In some embodiments, the deep ultraviolet microcavity laser comprises 45SiO₂-15Al₂O₃-12Na₂O、45SiO₂-15Al₂O₃-16NaF、30SiO₂-20Al₂O₃-10Bi₂O₃、45SiO₂-15Al₂O₃-12Na₂CO₃Any one of the microcrystalline glass carrier and rare earth nano crystal with the grain diameter of 10-50 nanometers growing inside the microcrystalline glass carrier, wherein the rare earth nano crystal comprises NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄At least one of a nanocrystal support and Ho³⁺、Tm³⁺And Yb, and³⁺and Gd³⁺Rare earth ions.

In the deep ultraviolet micro-cavity laser, the molar ratio of the microcrystalline glass carrier to the rare earth nanocrystal is (1-2): (1-5). In the deep ultraviolet micro-cavity laser provided by the embodiment of the invention, the molar ratio of the microcrystalline glass carrier to the rare earth nanocrystal is (1-2): (1-5), the molar ratio is most favorable for the direct growth of the rare earth nanocrystals in the glass ceramics to form crystals of 10-50 nm, if the molar ratio of the rare earth nanocrystals is too high, the rare earth nanocrystals in the glass ceramics are easy to agglomerate, the dispersion uniformity is poor, the light transmittance of the laser is affected, the laser with poor light transmittance is not favorable for exciting rare earth ions by exciting light, is not favorable for light conduction in the laser, and has large light loss and low light emitting efficiency; if the molar ratio of the rare earth nanocrystals is too low, the upconversion luminescence efficiency of rare earth ions in the microcavity laser is reduced. In some embodiments, in the deep ultraviolet micro-cavity laser, a molar ratio of the glass-ceramic support to the rare earth nanocrystals may be 1:1, 2:1, 1:2, 1:3, 1:5, 2:3, or 2: 5.

As a preferred embodiment, the Yb is in the cation of the rare earth nanocrystal³⁺The mol percentage content of the active ingredients is 10 to 80 percent(ii) a The Ho³⁺And Tm³⁺The total mole percentage content of the active carbon is 0.1 to 15 percent; the Gd³⁺The molar percentage of the component (a) is 0-5%. In the embodiment of the invention, the rare earth cation can replace the cation in the nanocrystal carrier to form the rare earth nanocrystal, and Yb is contained in the cation of the rare earth nanocrystal³⁺The molar percentage content of the compound is 10 to 80 percent; the Ho³⁺And Tm³⁺The total mole percentage content of the active carbon is 0.1 to 15 percent; the Gd³⁺The molar percentage of the rare earth ions is 0-5%, and the micro-cavity laser can effectively emit deep ultraviolet light with different expected wave bands. Wherein if Ho³⁺And Tm³⁺Too high a total mole percentage content of (b) may result in quenching between rare earth ions, which may reduce the up-conversion luminescence efficiency; gd (Gd)³⁺Can increase the content of Ho³⁺And Tm³⁺The light emitting selectivity of the rare earth ions realizes the emission of deeper ultraviolet laser.

In some embodiments, the rare earth nanocrystals comprise Yb³⁺、Ho³⁺And Tm³⁺Rare earth ion, wherein Yb is in the cation of the rare earth nanocrystal³⁺The molar percentage content of the compound is 10 to 80 percent; the Ho³⁺And Tm³⁺The total mole percentage content of the active carbon is 0.1 to 15 percent. In other embodiments, the rare earth nanocrystals comprise Yb³⁺And Ho³⁺Rare earth ion, wherein Yb is in the cation of the rare earth nanocrystal³⁺The molar percentage content of the compound is 10 to 80 percent; the Ho³⁺The mole percentage content of the compound is 0.1 to 15 percent. In other embodiments, the rare earth nanocrystals comprise Yb³⁺And Tm³⁺Rare earth ion, wherein Yb is in the cation of the rare earth nanocrystal³⁺The molar percentage content of the compound is 10 to 80 percent; the Tm is described³⁺The mole percentage content of the compound is 0.1 to 15 percent.

As a preferred embodiment, the deep ultraviolet micro-cavity laser is a cylinder with the length of 0.5-5 micrometers and the diameter of 20-500 nanometers. The deep ultraviolet microcavity laser is a cylindrical F-P resonant microcavity with the length of 0.5-5 microns and the diameter of 20-500 nanometers, emitted light is limited in the microcavity, the threshold for achieving laser emission is reduced, and deep ultraviolet emission is achieved better. The length and the diameter of the micro-cavity laser affect the emission of deep ultraviolet excitation light, if the diameter of the micro-cavity laser is too large or the length of the micro-cavity laser is too long, the ultraviolet excitation light is easy to scatter in the micro-cavity, the light loss is large, the energy consumption is large, and the laser is difficult to emit; if the diameter of the micro-cavity laser is too small or the length of the micro-cavity laser is too short, the larger the energy threshold required for ultraviolet laser emission is, the more difficult the emission is. In some embodiments, the length of the deep ultraviolet microcavity laser can be 0.5 microns, 1 micron, 2 microns, 3 microns, 4 microns, or 5 microns; the diameter may be 20 nanometers, 50 nanometers, 100 nanometers, 200 nanometers, 300 nanometers, 400 nanometers, or 500 nanometers.

As a preferred embodiment, the two ends of the deep ultraviolet micro-cavity laser are deposited with first Bragg reflecting layers with reflectivity of 75% -95% for 200-300 nanometer wave bands. According to the embodiment of the invention, the two ends of the deep ultraviolet microcavity laser are deposited with the first Bragg reflecting layer DBRs with the reflectivity of 75% -95% for the 200-300 nanometer waveband, in the microcavity laser, 980 nanometer exciting light excites rare earth ions to realize deep ultraviolet laser emission, the excited deep ultraviolet light continuously accumulates energy in a microcavity, and the laser deep ultraviolet emission is realized when the energy reaches an excitation threshold value. According to the embodiment of the invention, part of deep ultraviolet excitation light is reflected by the first Bragg reflection layer with the reflectivity of 75% -95% at the waveband of 200-300 nanometers, and the deep ultraviolet excitation light passes through the first Bragg reflection layer and is emitted from the micro-cavity laser after a carrier of the deep ultraviolet excitation light in the laser reaches a certain threshold value, so that the deep ultraviolet laser emission is better realized, and the up-conversion emission efficiency of rare earth on deep ultraviolet is improved. If the reflectivity is too high, the deep ultraviolet light excited by the rare earth ions can be limited in the laser, signals cannot be collected, and deep ultraviolet laser emission cannot be realized; if the reflectivity is too low, the deep ultraviolet light excited by the rare earth ions is seriously lost in the laser, and the deep ultraviolet laser emission is not easy to realize. In the embodiment of the invention, the reflectivity of the first Bragg reflection layer to a specific expected wave band in 200-300 nanometers can be 75% -95%. In some embodiments, the deep ultraviolet micro-cavity laser is deposited with a first bragg reflector layer with 75%, 80%, 85%, 90% or 95% reflectivity at 262nm band at both ends.

As a more preferable embodiment, a second bragg reflection layer with a reflectivity of 100% for an undesired waveband is further disposed on a surface of the first bragg reflection layer on a side far away from the deep ultraviolet microcavity laser cavity. In the embodiment of the present invention, a second bragg reflection layer having a reflectivity of 100% to an undesired waveband is further disposed on a surface of the first bragg reflection layer on a side away from the deep ultraviolet microcavity laser cavity, after the rare earth ions are excited by the excitation light, light of other wavebands is excited while emitting a desired deep ultraviolet waveband, and the wavebands except the light of the desired waveband are undesired wavebands, such as: tm is³⁺Besides emitting deep ultraviolet light less than 200 nanometers, excitation light in a 360nm waveband and excitation light in non-ultraviolet wavebands such as 450nm and 705nm exist; ho³⁺Light in a non-ultraviolet wave band such as 550nm is excited; in addition, when the desired excitation wavelength band is 260nm, other light such as 290nm, 340nm, 360nm, 450nm, etc. which is excited, is not desired. However, the light in the undesired waveband is not the waveband required by the target deep ultraviolet microcavity laser, so that the light in the undesired waveband is limited inside the laser by the second bragg reflection layer with the reflectivity of 100% of the undesired waveband, energy is transferred to the deep ultraviolet excitation light in a capacity transfer mode, carriers of the deep ultraviolet excitation light are promoted to reach an excitation threshold value to realize deep ultraviolet laser emission, unnecessary energy waste caused by the fact that the light in the undesired waveband penetrates out of the microcavity is avoided, and the up-conversion excitation efficiency of the microcavity laser is improved. The second bragg reflection layer can be provided with a plurality of layers according to the number of wave bands needing total reflection in practice.

In some embodiments, a second bragg reflection layer with a reflectivity of 100% for a 290nm, 340nm, 360nm, 450nm, 550nm or 800 nm band is further disposed on a surface of the first bragg reflection layer on a side away from the deep ultraviolet microcavity laser cavity, and at this time, the second bragg reflection layer has 6 layers, including a bragg reflection layer totally reflected at 290nm, a bragg reflection layer totally reflected at 340nm, a bragg reflection layer totally reflected at 360nm, a bragg reflection layer totally reflected at 450nm, a bragg reflection layer totally reflected at 550nm and a bragg reflection layer totally reflected at 800 nm.

As shown in FIG. 1, in some embodiments, 45SiO is included₂-15Al₂O₃-12Na₂O、45SiO₂-15Al₂O₃-16NaF、30SiO₂-20Al₂O₃-10Bi₂O₃、45SiO₂-15Al₂O₃-12Na₂CO₃Any one of the microcrystalline glass carrier, rare earth nanocrystals which grow in the microcrystalline glass carrier and have the grain size of 10-50 nanometers, and Bragg reflecting layers deposited at two ends; wherein the rare earth nanocrystals comprise NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄At least one of a nanocrystal support and Ho³⁺、Tm³⁺And Yb, and³⁺and Gd³⁺Rare earth ions; the Bragg reflection layer comprises a first Bragg reflection layer which is deposited at two ends of the deep ultraviolet micro-cavity laser and has 75% -95% of reflectivity in 200-300 nanometer wave bands and a second Bragg reflection layer which is deposited on the surface of the first Bragg reflection layer and has 100% of reflectivity in undesired wave bands.

The deep ultraviolet micro-cavity laser provided by the embodiment of the invention can be prepared by the following method.

The embodiment of the invention also provides a preparation method of the deep ultraviolet micro-cavity laser, which comprises the following steps:

s10, obtaining a microcrystalline glass carrier material, a nanocrystalline carrier material and a rare earth ion precursor, mixing the microcrystalline glass carrier material, the nanocrystalline carrier material and the rare earth ion precursor, and then carrying out high-temperature calcination treatment to obtain amorphous glass;

s20, drawing the amorphous glass, annealing at high temperature, and cooling to obtain a glass optical fiber;

and S30, after the glass optical fiber is cut, depositing a Bragg reflection layer on the cutting surface of the glass optical fiber to obtain the deep ultraviolet microcavity laser.

The preparation method of the deep ultraviolet micro-cavity laser provided by the embodiment of the invention comprises the steps of mixing a microcrystalline glass carrier material, a nanocrystalline carrier material and a rare earth ion precursor, and then calcining the mixture at a high temperature to obtain amorphous glass, so that the raw material components are melted and mixed; then melting and drawing the amorphous glass, then carrying out high-temperature annealing treatment to separate out uniformly distributed rare earth nanocrystals from the microcrystalline glass carrier, and cooling to obtain the glass optical fiber; and cutting the glass fiber into a certain length to form an F-P resonant microcavity, and depositing a Bragg reflection layer on the cutting surface to obtain the deep ultraviolet microcavity laser. According to the preparation method of the deep ultraviolet microcavity laser, microcrystalline glass is used as a carrier material, rare earth ions directly precipitate rare earth nanocrystals in the microcrystalline glass carrier through the nanocrystalline carrier, and the rare earth nanocrystals directly grow and precipitate in the microcrystalline glass, so that the rare earth nanocrystals and the microcrystalline glass carrier are good in combination stability, and the microcrystalline glass carrier material has excellent thermal stability, chemical stability, mechanical strength and the like, so that the prepared deep ultraviolet microcavity laser is good in thermal-chemical stability, good in excitation resistance and high in excitation efficiency, and the deep ultraviolet laser emission is better realized.

Specifically, in step S10, a microcrystalline glass carrier material, a nanocrystalline carrier material, and a rare earth ion precursor are obtained, and after the microcrystalline glass carrier material, the nanocrystalline carrier material, and the rare earth ion precursor are mixed, the mixture is subjected to high-temperature calcination treatment to obtain amorphous glass. In the embodiment of the invention, the microcrystalline glass carrier material, the nanocrystalline carrier material and the rare earth ion precursor are used as raw materials to prepare the microcavity laser, wherein the rare earth ion precursor is an oxide of rare earth metal, and the action and the characteristics of each raw material are discussed in detail in the previous section and are not repeated herein.

As a preferred embodiment, after the microcrystalline glass carrier material, the nanocrystalline carrier material and the rare earth ion precursor are mixed, the mixture is calcined at high temperature for 1-3 hours in an atmosphere at 1300-1650 ℃, so that the raw material components form an amorphous body which is uniformly mixed.

In some embodiments, the rare earth ion precursor comprises: yb of₂O₃And Ho₂O₃And/or Tm₂O₃An oxide of a rare earth ion of (1). In other embodiments, the rare earth ion precursor comprises: yb of₂O₃And Ho₂O₃And/or Tm₂O₃And Gd₂O₃An oxide of a rare earth ion of (1).

In some embodiments, the nanocrystalline support material includes, but is not limited to, NaYF₄、CaF₂、Ba₂LaF₇、LaF₃、NaGdF₄At least one material of (1).

In some embodiments, the microcrystalline glass support material includes, but is not limited to, 45SiO₂-15Al₂O₃-12Na₂O、45SiO₂-15Al₂O₃-16NaF、30SiO₂-20Al₂O₃-10Bi₂O₃、45SiO₂-15Al₂O₃-12Na₂CO₃Any one of the above materials.

Specifically, in step S20, the amorphous glass is drawn, annealed at a high temperature, and cooled to obtain a glass optical fiber. In the embodiment of the invention, after the amorphous glass is drawn into the optical fiber, the rare earth in the amorphous glass is combined with the nanocrystalline carrier and precipitated in the form of the nanocrystalline by a high-temperature annealing mode, so that a necessary substrate cavity is provided for rare earth excited light.

As a preferred embodiment, the step of annealing the amorphous glass at high temperature after drawing the amorphous glass comprises: and after the amorphous glass is subjected to melt wire drawing, annealing for 1-3 hours at the temperature of 300-700 ℃, and separating out the rare earth nanocrystals. In the embodiment of the invention, after the amorphous glass is subjected to melt wire drawing, annealing is carried out for 1-3 hours at the temperature of 300-700 ℃, so that uniformly dispersed rare earth nanocrystals are precipitated from the amorphous glass. If the annealing temperature is too high, other impurity phases can be additionally precipitated, and the rare earth nanocrystals can be agglomerated, so that the luminous efficiency of the microcavity laser is affected. If the annealing temperature is too low, the nucleation temperature of the rare earth nanocrystals cannot be reached, and the rare earth nanocrystals cannot be separated out. In some embodiments, the step of high temperature annealing after drawing the amorphous glass comprises: and after the amorphous glass is subjected to melt wire drawing, annealing for 1-3 hours at the temperature of 300 ℃, 400 ℃, 500 ℃, 600 ℃ or 700 ℃, and separating out the rare earth nanocrystal.

Specifically, in step S30, after the glass optical fiber is cut, a bragg reflection layer is deposited on a cut surface of the glass optical fiber, so as to obtain the deep ultraviolet microcavity laser. According to the embodiment of the invention, the glass fiber is cut into a certain length to form the F-P resonant microcavity, the F-P resonant microcavity is used for realizing laser emission, then the Bragg reflection layer is deposited on the cut surface, and the microcavity laser can better emit deep ultraviolet light through the Bragg reflection layer.

As a preferred embodiment, the step of depositing a bragg reflective layer on the cut surface of the glass optical fiber after the glass optical fiber is cut comprises: and cutting the glass optical fiber into a cylindrical shape, and depositing first Bragg reflecting layers with the reflectivity of 75% -95% for 200-300 nanometer wave bands on cutting surfaces at two ends of the glass optical fiber. According to the embodiment of the invention, the glass optical fiber is cut into a cylindrical shape, the first Bragg reflecting layer with the reflectivity of 75% -95% to the 200-300 nanometer wave band is deposited on the cutting surfaces at the two ends of the glass optical fiber, part of deep ultraviolet exciting light is reflected through the first Bragg reflecting layer, and when the carrier of the deep ultraviolet exciting light in the laser reaches a certain threshold value, the deep ultraviolet exciting light penetrates through the first Bragg reflecting layer and is emitted from the microcavity laser, so that the deep ultraviolet laser emission is better realized.

As a preferred embodiment, the step of depositing a bragg reflective layer on the cut surface of the glass optical fiber further comprises: and depositing a second Bragg reflection layer with the reflectivity of 100% for the undesired waveband on the surface of the first Bragg reflection layer far away from the glass optical fiber. The embodiment of the invention also comprises a second Bragg reflecting layer with the reflectivity of 100 percent to the undesired wave band is deposited on the surface of one side of the first Bragg reflecting layer far away from the glass optical fiber, the light of the undesired wave band is limited in the laser through the second Bragg reflecting layer, the energy is transferred to the deep ultraviolet exciting light in a capacity transfer mode, the carrier of the deep ultraviolet exciting light is promoted to reach the excitation threshold value to realize the emission of the deep ultraviolet laser, the unnecessary energy waste caused by the fact that the light of the undesired wave band penetrates out of the microcavity is avoided, and the conversion excitation efficiency on the microcavity laser is improved.

As a preferred embodiment, the diameter of the deep ultraviolet micro-cavity laser is 20-500 nanometers, and the length of the deep ultraviolet micro-cavity laser is 0.5-5 millimeters. According to the embodiment of the invention, amorphous glass is drawn into the optical fiber with the diameter of 20-500 nanometers, and the optical fiber is cut into the length of 0.5-5 millimeters after annealing to separate out the rare earth nanocrystals, so that an F-P resonance microcavity is provided for realizing deep ultraviolet laser emission, emitted light is limited in the microcavity, and the threshold for realizing laser emission is reduced.

In some embodiments, the method for preparing the deep ultraviolet micro-cavity laser comprises the following steps:

s11, obtaining a microcrystalline glass carrier material, a nanocrystalline carrier material and a rare earth ion precursor, mixing the microcrystalline glass carrier material, the nanocrystalline carrier material and the rare earth ion precursor, and calcining at high temperature for 1-3 hours in an atmosphere at 1300-1650 ℃ to obtain amorphous glass;

s12, drawing the amorphous glass into an optical fiber with the diameter of 20-500 nanometers, annealing for 1-3 hours at the temperature of 300-700 ℃, separating out rare earth nanocrystals, and cooling to obtain the glass optical fiber;

s13, cutting the glass optical fiber into a cylinder with the length of 0.5-5 microns, depositing a first Bragg reflection layer with the reflectivity of 75% -95% for 200-300 nanometer wave bands on cutting surfaces at two ends of the glass optical fiber, and depositing a second Bragg reflection layer with the reflectivity of 100% for undesired wave bands on the surface of one side, away from the glass optical fiber, of the first Bragg reflection layer to obtain the deep ultraviolet microcavity laser.

In order to make the above implementation details and operations of the present invention clearly understood by those skilled in the art and obviously show the advanced performance of the deep ultraviolet micro-cavity laser and the manufacturing method thereof according to the embodiments of the present invention, the above technical solution is illustrated by a plurality of embodiments.

Example 1

A deep ultraviolet micro-cavity laser comprises the following preparation steps:

obtaining 45SiO₂-15Al₂O₃-12Na₂CO₃、Ba₂LaF₇、Yb₂O₃，Tm₂O₃The materials are mixed and then calcined for 2 hours at the high temperature of 1550 ℃ in the atmosphere, so that amorphous glass is obtained;

heating the amorphous glass on an alcohol lamp for 20 minutes to change the amorphous glass into a molten state, then clamping two ends of the amorphous glass by two tweezers, placing the amorphous glass on the alcohol lamp, heating the amorphous glass at a high temperature until the amorphous glass is molten, and pulling the two ends of the amorphous glass away by the tweezers to enable the amorphous glass in the middle molten state to form an optical fiber with the diameter of 500 micrometers; putting the optical fiber into an annealing furnace for high-temperature annealing treatment at 600 ℃ to precipitate Ba₂LaF₇:Yb³⁺，Tm³⁺Nano-crystals, and then cooling to room temperature to obtain a glass optical fiber;

and thirdly, cutting the glass optical fiber to the glass optical fiber with two smooth ends by using laser, wherein the length of the optical fiber is 2 mm, spraying a Bragg reflection layer film material on the two smooth ends of the cut glass, the reflectivity is 85%, and the glass optical fiber is used for high-reflection 262nm luminescence to obtain the glass optical fiber with high-reflection 262nm luminescence.

And fourthly, spraying five layers of Bragg reflection layer film materials at two ends of the glass optical fiber with high reflection 262 nanometer luminescence, and respectively performing total reflection on the glass optical fiber with high reflection 262 nanometer luminescence to emit light at 290nm, 340nm, 360nm, 450nm and 470nm to obtain the deep ultraviolet microcavity laser.

Further, to verify the advancement of the preparation of the inventive examples, the inventive examples were subjected to spectroscopic testing.

In the deep ultraviolet micro-cavity laser prepared by the embodiment of the invention, the excitation light density at 980nm is respectively 2 mJ/cm²，3 mJ/cm²，4 mJ/cm²And 5mJ/cm²Excited under the condition of laser emitting lightThe spectrum is shown in FIG. 2 (the excitation light density of 980nm from top to bottom is 2 mJ/cm in sequence)²，3 mJ/cm²，4mJ/cm²And 5mJ/cm²) As can be seen from the laser spectrum chart 2, the deep ultraviolet microcavity laser prepared in example 1 can realize upconversion laser emission at 262nm, the half-peak width of the emission can reach 0.21 nm, and the upconversion excitation efficiency is high.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.