阅读说明：本技术 一种钒酸铯红外倍频晶体材料及其制备与应用 (Cesium vanadate infrared frequency doubling crystal material and preparation and application thereof ) 是由 张弛 吴超 林霖 于 2020-06-19 设计创作，主要内容包括：本发明涉及一种钒酸铯红外倍频晶体材料及其制备与应用,该晶体材料的化学式为Cs<Sub>2</Sub>V<Sub>4</Sub>O<Sub>11</Sub>,属于正交晶系,空间群为Pca2<Sub>1</Sub>,晶胞参数为<Image he="71" wi="501" file="DDA0002546873960000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image><Image he="55" wi="700" file="DDA0002546873960000012.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>α＝β＝γ＝90°,Z＝2,<Image he="69" wi="435" file="DDA0002546873960000013.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>与现有技术相比,本发明的钒酸铯材料具有较大的倍频效应,在1064nm激光照射下,粉末倍频强度约为KH<Sub>2</Sub>PO<Sub>4</Sub>(KDP)晶体的12倍；在2.10μm激光照射下测得粉末倍频效应强度约为AgGaS<Sub>2</Sub>晶体的2.2倍。在波长1064nm的激光下测得激光损伤阈值为已商业化的红外二阶非线性光学晶体材料AgGaS<Sub>2</Sub>的24倍。此外,该晶体材料在可见光和红外区有很宽的光学透过范围,完全透过波段为0.33～14.80μm,在激光频率转换、光电调制、激光信号全息储存等领域具有广泛的应用前景。(The invention relates to a cesium vanadate infrared frequency doubling crystal material and preparation and application thereof, wherein the chemical formula of the crystal material is Cs 2 V 4 O 11 Belonging to the orthorhombic system, and having a space group of Pca2 1 Cell parameter of α＝β＝γ＝90°，Z＝2， Compared with the prior art, the cesium vanadate material has a larger frequency doubling effect, and the powder frequency doubling intensity is about KH under 1064nm laser irradiation 2 PO 4 12 times as large (KDP) crystals; the powder frequency doubling effect intensity measured under 2.10 mu m laser irradiation is about AgGaS 2 2.2 times of the crystal. The laser damage threshold value measured under laser with the wavelength of 1064nm is the commercialized infrared second-order nonlinear optical crystal material AgGaS 2 24 times higher than the first. In addition, the crystal material has wide optical transmission range in visible light and infrared regions, the complete transmission waveband is 0.33-14.80 mu m, and the crystal material has wide application prospects in the fields of laser frequency conversion, photoelectric modulation, laser signal holographic storage and the like.)

1. The cesium vanadate infrared frequency doubling crystal material is characterized in that the chemical formula of the crystal material is Cs ₂V₄O₁₁。

2. The cesium vanadate infrared frequency doubling crystal material according to claim 1, belonging to an orthorhombic system, and having a space group of Pca2₁Cell parameter of

3. The method for preparing the cesium vanadate infrared frequency doubling crystal material according to claim 1 or 2, which is characterized by comprising the following steps of:

(1) mixing a cesium source, a vanadium source, a mineralizer, hydrofluoric acid and water to form an initial mixed raw material;

(2) and (2) crystallizing the initial mixed raw materials in the step (1) under a hydrothermal condition to obtain a target product.

4. The method for preparing cesium vanadate infrared frequency doubling crystal material according to claim 3, wherein the cesium source is at least one selected from cesium carbonate, cesium hydroxide, cesium fluoride, cesium chloride or cesium nitrate.

5. The method for preparing cesium vanadate infrared frequency doubling crystal material according to claim 3, wherein the vanadium source is at least one selected from vanadium pentoxide, ammonium metavanadate, vanadium powder or sodium metavanadate.

6. The method for preparing cesium vanadate infrared frequency doubling crystal material according to claim 3, wherein the mineralizer is selected from at least one of sodium bromate and potassium bromate.

7. The method for preparing cesium vanadate infrared frequency doubling crystal material according to claim 3, wherein in the step (1), the addition amounts of cesium source, vanadium source, mineralizer and hydrofluoric acid in the initial mixed raw materials are as follows: the mol ratio of the cesium element, the vanadium element, the mineralizer and the hydrofluoric acid is 2 (0.1-2) to 0.1-2 (0.1-1).

8. The method for preparing cesium vanadate infrared frequency doubling crystal material according to claim 3, wherein the molar concentration of cesium in the initial mixed raw materials in the step (1) is 0.01-2 mol/L.

9. The method for preparing cesium vanadate infrared frequency doubling crystal material according to claim 3, wherein in the step (2), the temperature of hydrothermal conditions is 200-220 ℃, and the crystallization time is not less than 24 h.

10. Use of cesium vanadate infrared frequency doubling crystal material according to claim 1 or 2 in a laser frequency converter.

Technical Field

The invention belongs to the technical field of optical crystal materials, and relates to a cesium vanadate infrared frequency doubling crystal material and preparation and application thereof.

Background

The second-order nonlinear optical crystal is typically characterized by frequency doubling effect (SHG), is an important photoelectric functional material, and has important application prospects in the fields of laser frequency conversion, photoelectric modulation, laser signal holographic storage and the like. According to the light-transmitting band and the application range, the inorganic nonlinear optical crystal material can be divided into a nonlinear optical material in an ultraviolet light region, a nonlinear optical material in a visible light region and a nonlinear optical material in an infrared light region. Currently commercialized nonlinear optical materials in the ultraviolet and visible light regions are BBO (β -barium metaborate), LBO (lithium borate), KDP (potassium dihydrogen phosphate), KTP (potassium titanyl phosphate), and the like. However, there is still a gap in the practical application of the nonlinear optical material in the infrared region compared to the commercialized ultraviolet and visible region materials, because of the existing nonlinear optical material, such as AgGaS₂、AgGaSe₂However, the synthesis conditions are severe, and the single crystal is not easily grown to have a large optical quality, and particularly, the problem of the laser damage threshold being too low is not satisfactory for practical use. Therefore, the research on the infrared optical frequency doubling crystal material has become An important research direction in the field of inorganic materials has been advanced.

For example, patent CN101871125A discloses a series of rare earth oxide laser crystal materials having the following formula: (Ln)_xRe_1-x)O₃X is more than 0 and less than 0.3, wherein Ln ═ Yb, Tm, Nd, Er, Ho and Yb_yEr_1-yOr Tm_yHo_1-y；0＜y＜1；Re＝Lu,Sc,Lu_zY_1-zOr Sc_zY_1-z(ii) a Z is more than 0 and less than 0.3. The crystal material disclosed by the patent has high transparency, but the light transmission range is narrow, so that the application requirement of the infrared second-order nonlinear optical crystal is difficult to meet.

In addition, for example, Chinese patent ZL200710126779.1 discloses a novel infrared nonlinear crystal cesium vanadate with molecular formula CsV₂O₅CsV of the compound₂O₅Is about 6 times that of KDP and is phase mismatched.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide a cesium vanadate infrared frequency doubling crystal material and preparation and application thereof.

The purpose of the invention can be realized by the following technical scheme:

one of the technical schemes of the invention provides a cesium vanadate infrared frequency doubling crystal material with a chemical formula of Cs₂V₄O₁₁。

Further, the crystalline material belongs to an orthorhombic system, and the space group is Pca2₁Cell parameter of

α＝β＝γ＝90°，Z＝2，

The crystal structure of the cesium vanadate material is as follows: each asymmetric unit contains two Cs atoms, four V atoms and eleven O atoms. Each Cs atom is connected with twelve O atoms to form a polyhedron, and two V atoms are respectively connected with four and five O atoms to form VO ₄Tetrahedron and VO₅A pentahedron. VO (vacuum vapor volume)₄And VO₅The polyhedron forms a two-dimensional honeycomb type layer structure on the ab surface in a connection mode of common points or common edges. The counter cation cesium is between the vanadium oxide layers. VO (vacuum vapor volume)₄And VO₅The polyhedrons are substantially uniformly arranged in the c-axis direction. This arrangement is advantageous in increasing the polarity of the compound and thus its nonlinear optical coefficient.

The second technical scheme of the invention provides a preparation method of a cesium vanadate infrared frequency doubling crystal material, which comprises the following steps:

(1) mixing a cesium source, a vanadium source, a mineralizer, hydrofluoric acid and water to form an initial mixed raw material;

(2) and (2) crystallizing the initial mixed raw materials in the step (1) under a hydrothermal condition to obtain a target product.

Further, the cesium source is at least one selected from cesium carbonate, cesium hydroxide, cesium fluoride, cesium chloride and cesium nitrate.

Further, the vanadium source is at least one selected from vanadium pentoxide, ammonium metavanadate, vanadium powder and sodium metavanadate.

Further, the mineralizer is selected from at least one of sodium bromate and potassium bromate.

Further, in the step (1), the addition amounts of the cesium source, the vanadium source, the mineralizer and the hydrofluoric acid in the initial mixed raw materials satisfy: the mol ratio of the cesium element, the vanadium element, the mineralizer and the hydrofluoric acid is 2 (0.1-2) to 0.1-2 (0.1-1).

Further, in the initial mixed raw material in the step (1), the molar concentration of the cesium element is 0.01-2 mol/L.

Further, in the step (2), the temperature of the hydrothermal condition is 200-220 ℃, and the crystallization time is not less than 24 hours.

Further, the reaction is carried out in a sealed reaction kettle.

In the hydrothermal reaction process, a high-temperature high-pressure state is formed in the sealed hydrothermal reaction kettle, natural forming conditions similar to geological rock minerals can be simulated, the dissolution and mixing of insoluble raw materials are facilitated, the chemical reaction rate and the crystallization rate are accelerated, and the crystal material is obtained through the heterogeneous reaction. Wherein, the introduction of the mineralizer and hydrofluoric acid can improve the reaction yield (see a comparative experiment). The kinds and addition amounts of the raw materials are consistent, and if the temperature is too high (higher than 220 ℃), the final reaction is favorable for CsV generation₃O₈Or Cs₃V₂O₃F₇(ii) a If the temperature is too low (below 220 degrees), the final reaction favors the formation of CsVO₃。

The third technical scheme of the invention provides the application of the cesium vanadate infrared frequency doubling crystal material in a laser frequency converter. The laser frequency converter is used for outputting visible light and infrared laser beams in double frequency harmonic waves.

The cesium vanadate crystal material prepared by the method has extremely strong frequency doubling effect and high laser damage threshold. The powder frequency doubling effect is about 12 times of KDP crystal under 1064nm laser irradiation, and the powder frequency doubling effect strength is AgGaS under 2.10 μm laser irradiation ₂2.2 times of the phase matching can be realized. The laser damage threshold is about the commercialized frequency doubling material AgGaS₂24 times of the crystal. In addition, the optical transmission range of the crystal material is 0.33-11.80 μm, and thermogravimetric tests show that the compound is a consistent melting compound.

Compared with the prior art, the invention has the following advantages:

(1) the cesium vanadate infrared frequency doubling crystal material has extremely strong frequency doubling effect and wide optical transmission range, the powder frequency doubling effect is about 12 times of that of KDP crystal under 1064nm laser irradiation, and the powder frequency doubling effect strength measured under 2.10 mu m laser irradiation is AgGaS₂2.2 times of the phase matching can be realized. The optical transmission range of the crystal material is 0.33-14.80 μm, and the crystal material can cover two middle infrared atmospheric windows (3-5 μm and 8-12 μm).

(2) The method adopts a hydrothermal method with mild reaction conditions, and can quickly obtain a high-purity sample through hydrothermal crystallization at the temperature of 100-220 ℃. The method is simple, the conditions are mild, the obtained material has good thermal stability, and the method is favorable for realizing large-scale industrial production.

(3) The cesium vanadate material can be applied to a laser frequency converter and can be used for outputting laser beams with the wavelength of 1064nm and the wavelength of 2.10 mu m as frequency-doubled harmonic waves.

Drawings

FIG. 1 shows Cs₂V₄O₁₁A schematic of the crystal structure of (a);

FIG. 2 is a comparison of X-ray diffraction patterns; wherein (a) is a powder X-ray diffraction pattern obtained by the crystal structure analyzed by sample No. 1 according to single crystal X-ray diffraction data and fitting; (b) is a spectrum obtained by X-ray diffraction test after a sample No. 1 is ground into powder;

FIG. 3 is an ultraviolet-visible-near infrared absorption spectrum of sample # 1;

FIG. 4 is an infrared spectrum, IR (2.5 to 25 μm) spectrum, of sample # 1;

FIG. 5 is a thermogravimetric analysis plot of sample # 1;

FIG. 6 is a plot of the second harmonic signals for sample 1# and a standard KDP sample size in the range of 105-150 μm;

FIG. 7 is a graph of second harmonic phase matching for sample # 1 at 1.064 μm wavelength band;

FIG. 8 is sample No. 1 and the standard AgGaS₂A second harmonic signal diagram with the sample size within the range of 105-150 mu m;

fig. 9 is a graph of second harmonic phase matching for sample 1# in the 2.10 μm band.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.

In the following examples, HF is a conventional commercially available hydrofluoric acid product (i.e., 40% by weight), and unless otherwise specified, raw materials or processing techniques are all conventional commercially available products or conventional processing techniques in the art.