A type of sulfur oxide crystal material and its preparation method and application as infrared nonlinear optical material

Abstract

This application discloses a class of sulfide compound crystal materials and their preparation methods and applications as infrared nonlinear optical materials, belonging to the field of crystal preparation technology. The chemical formula of the sulfide compound crystal material is A8Na2M 30 Q 45 O5; where A is selected from at least one of K, Rb, and Cs; M is selected from at least one of Ga and In; and Q is selected from at least one of S and Se. This crystal material has an NLO effect 0.3-5 times that of AgGaS2 and a laser damage threshold 1-50 times that of AgGaS2, significantly improving its overall performance and making it a potential infrared NLO material.

Description

Technical Field

[0001] The present application relates to a type of sulfur oxide crystal material, a preparation method thereof, and an application thereof as an infrared nonlinear optical material, and belongs to the field of crystal preparation technology. Background Art

[0002] Nonlinear optical (NLO) materials significantly extend the output spectral range of laser sources through frequency conversion, which has wide application demands in both civilian and military fields. Inorganic chalcogenides are among the most promising candidates for mid-infrared (MIIR) NLO materials. These materials have infrared absorption edges extending to approximately 10 μm and exhibit good transmittance within the first atmospheric transparency window (3 to 5 μm). Many metal sulfides exhibit strong NLO effects, but achieving high-performance materials that combine a large bandgap (Eg) with efficient second harmonic generation (SHG) response remains a major challenge. Currently, although a few chalcopyrite-structured materials (e.g., AgGaS2, AgGaSe2, and ZnGeP2) have been commercialized in the IR region, these materials all have inherent defects. Therefore, there is an urgent need to develop novel MIR NLO materials that possess balanced properties, including appropriate birefringence for phase matching, large frequency-shock effects, wide bandgap for high laser damage thresholds, broad transmittance range, and excellent physical and chemical stability. These properties are crucial for promoting the further development of mid-infrared NLO materials in high-performance lasers and related technologies. Summary of the Invention

[0003] In order to solve the problem in the existing technology of mid-infrared nonlinear optical (NLO) crystals that it is difficult to balance a large NLO effect and a high laser damage threshold, the present application provides a class of sulfur oxide crystal materials, whose NLO effect is 0.3-5 times that of commercial AgGaS2, and the laser damage threshold is 1-50 times that of commercial AgGaS2. The comprehensive performance is greatly improved, and it is a potential infrared NLO material.

[0004] This application adopts the following scheme:

[0005] A type of sulfur oxide crystal material, the chemical formula of the type of sulfur oxide crystal material is A8Na2M 30 Q 45 O5;

[0006] wherein A is selected from at least one of K, Rb, and Cs;

[0007] M is selected from at least one of Ga and In;

[0008] Q is selected from at least one of S and Se.

[0009] Optionally, the type of sulfur oxide crystal material has a diamond-like structure, that is, the tetrahedral structural units are connected by common points of anions to form a three-dimensional honeycomb-like hexagonal open pore-like framework.

[0010] Optionally, the type of sulfur oxide crystal material belongs to the P-62c space group of the hexagonal system.

[0011] Optionally, the unit cell parameters of the type of sulfur oxide crystal material are α=β=90.0°, γ=120.0°,

[0012] Optionally, the laser damage threshold of the type of oxysulfide crystal material powder is 1 to 50 times that of AgGaS2.

[0013] Optionally, the laser damage threshold of the salt-containing chalcogenide compound crystal material powder is 10 to 45 times that of AgGaS2.

[0014] Optionally, the frequency harmonic intensity of the type of oxysulfide crystal material is 0.3 to 5 times that of AgGaS2.

[0015] Optionally, the double harmonic intensity of the salt-containing chalcogenide compound crystal material is 0.3-2.1 times that of AgGaS2.

[0016] According to another aspect of the present application, a method for preparing the above-mentioned type of sulfur oxide crystal material is provided, comprising the following steps:

[0017] A raw material mixture containing element A, element M, element Q, and NaX is placed in a reaction vessel, which is vacuum-sealed and heated to a reaction temperature to react to obtain the aforementioned type of sulfur oxide crystal material;

[0018] Wherein, X in NaX is selected from at least one of Cl, Br, and I.

[0019] Optionally, the raw materials containing element A, element M, element Q and NaCl are prepared in a molar ratio of A:M:M2O3:Q:NaX=1:(4-5):(1-2):(6-9):(3-6) and mixed uniformly to obtain the product.

[0020] Optionally, in the raw material mixture, the source of element A is selected from element A.

[0021] The source of the M element is selected from at least one of M element and M2O3.

[0022] The source of the Q element is selected from Q simple substance.

[0023] Optionally, the reaction conditions are:

[0024] The reaction temperature is 600° C. to 1000° C., and the reaction time is 1 h to 100 h.

[0025] Optionally, the reaction temperature is reached by heating, and the heating rate is 1° C. / h to 60° C. / h.

[0026] Optionally, cooling is required after the reaction;

[0027] The cooling is performed by natural cooling or cooling to 300°C to 400°C at a cooling rate of 1°C / h-10°C / h and then naturally cooling.

[0028] Optionally, the pressure range of the reaction container after vacuuming is 10 -3 Pa-10Pa.

[0029] Optionally, the sealing method is welding sealing.

[0030] Optionally, the reaction container is a quartz tube.

[0031] According to another aspect of the present application, there is also provided an application of the above-mentioned type of sulfur oxide crystal material or the type of sulfur oxide crystal material obtained according to the above-mentioned preparation method as a nonlinear optical crystal in the laser field.

[0032] The beneficial effects of this application include:

[0033] The present application provides a class of oxysulfide crystal materials, which have a frequency doubling effect of 0.3-5 times that of commercial AgGaS2 and a laser damage threshold of 1-50 times that of commercial AgGaS2, with greatly improved performance, and are potential infrared nonlinear optical materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 K8Na2Ga prepared in this embodiment 30 S 45 Powder diffraction pattern of O5;

[0035] Figure 2 K8Na2Ga at 1910nm 30 S 45 O5、Rb8Na2Ga 30 Se 45 O5、Cs8Na2In 30 Se 45 O5、Rb8Na2In 30 Se 45 Frequency-doubled signals of O5 and AgGaS2 polycrystalline powders;

[0036] Figure 3 K8Na2Ga prepared in this embodiment30 S 45 Crystal structure of O5. DETAILED DESCRIPTION

[0037] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0038] Unless otherwise specified, the raw materials in the examples of this application were purchased through commercial channels.

[0039] The instrument used for single crystal X-ray diffraction was Rigaku FR-X microfocus diffractometer;

[0040] Test conditions: 293K, structure analysis using SHELXTL crystallography software.

[0041] The instrument used for powder X-ray diffraction was Rigaku Flex600 X-ray diffractometer;

[0042] Test conditions: 293K.

[0043] The laser damage threshold calculation method described in this application utilizes a VIBRANTHE 355LD laser instrument manufactured by OPOTEK Corporation in the United States. First, Example 1 and commercially available AgGaS2 (Comparative Example 1) were screened to isolate particles with a size range of 150-200 nm. These particles were then placed in the path of a 1064 nm laser with a pulse width of 10 ns. The surface damage of the samples was observed by continuously increasing the laser power. The laser power was recorded until a damage spot appeared on the sample, and the size of the damage spot was measured. The laser damage threshold was then compared using the ratio of laser power to damage area.

[0044] The test method of the frequency doubling signal described in the present application is to use a standard sieve to screen the sample crystals and the AgGaS2 crystals used as a reference to obtain crystals with particle sizes in five ranges of 30-50, 50-75, 75-100, 100-150, and 150-200 nm, respectively, load the samples separately, place them under the laser light path, and use a near-infrared charge-coupled detector to test their nonlinear optical properties at a laser intensity of 1910 nm. Then, a graph is drawn with the particle size as the horizontal axis and the measured nonlinear optical properties as the vertical axis to determine the size of the nonlinear optical properties of the crystal material and the phase matching of the crystal material.

[0045] Example 1

[0046] K (18.6 mg), Ga (133.0 mg), Ga2O3 (90.0 mg), S (91.5 mg) and NaCl (167.0 mg) were mixed and placed in a quartz tube and evacuated to 10 -2The Pa tube was sealed and placed in a muffle furnace and slowly heated to 850°C. After keeping the temperature for 72 hours, the temperature was lowered to 300°C at 3°C / h. The muffle furnace was turned off and naturally cooled to room temperature to obtain the chemical formula K8Na2Ga 30 S 45 The powder diffraction pattern of the crystal is as follows: Figure 1 The crystal structure is shown in Figure 3 shown.

[0047] Example 2

[0048] Rb (24.0 mg), Ga (98.7 mg), Ga2O3 (54.7 mg), Se (158.5 mg) and NaI (184.1 mg) were mixed and placed in a quartz tube and evacuated to 10 -3 The Pa tube was sealed and placed in a muffle furnace and slowly heated to 950°C. After keeping the temperature for 12 hours, the temperature was lowered to 400°C at 4°C / h. The muffle furnace was turned off and naturally cooled to room temperature to obtain the chemical formula Rb8Na2Ga 30 Se 45 O5 crystal.

[0049] Example 3

[0050] Rb (23.4 mg), Ga (125.2 mg), Ga2O3 (76.0 mg), Se (151.5 mg) and NaBr (123.0 mg) were mixed and placed in a quartz tube, evacuated to 10 Pa and sealed. The tube was placed in a muffle furnace and slowly heated to 700 ° C. After keeping the temperature for several hundred hours, the temperature was lowered to 300 ° C at 5 ° C / h. The muffle furnace was turned off and naturally cooled to room temperature to obtain the chemical formula Rb8Na2Ga 30 Se 45 O5 crystal.

[0051] Example 4

[0052] Cs (26.8 mg), Ga (115.2 mg), Ga2O3 (116.2 mg), Se (141.5 mg) and NaBr (173.7 mg) were mixed and placed in a quartz tube, evacuated to 1 Pa and sealed. The tube was placed in a muffle furnace and slowly heated to 850°C. After keeping the temperature for 80 hours, the temperature was lowered to 300°C at 3°C / h. The muffle furnace was turned off and naturally cooled to room temperature to obtain the chemical formula Cs8Na2In 30 Se 45 O5 crystal.

[0053] Test Example 1

[0054] NLO performance test method: Use standard sieves to screen out crystals with particle sizes of 30-50, 50-75, 75-100, 100-150, and 150-200 nm from the sample crystals and the reference AgGaS2 crystals. Load the samples separately and place them under the laser light path. Use a near-infrared charge-coupled detector to test their nonlinear optical properties at a laser intensity of 1910 nm. Then, plot the particle size as the horizontal axis and the measured nonlinear optical performance as the vertical axis to determine the NLO performance of the crystal material and the phase matching of the crystal material.

[0055] Figure 2 It shows that K8Na2Ga 30 S 45 O 5, Rb8Na2Ga 30 Se 45 O5,Rb8Na2Ga 30 Se 45 O 5, Cs8Na2In 30 Se 45 The double frequency signals of the compound polycrystalline powder of O5 are 1.1, 1.2, 2.2 and 2.1 times that of AgGaS2 respectively, with a particle size of 150-200um at 1910nm.

[0056] Test Example 2

[0057] Laser damage threshold test of the sample: Use a standard sieve to screen out crystals with a particle size range of 150-200nm from the sample crystal and the AgGaS2 crystal used as a reference. Load the samples separately and place them under a 1064nm laser light path with a pulse width of 10ns. Continuously increase the laser power and observe the damage on the sample surface until a damage spot appears on the sample. Record the laser power at this time and measure the size of the damage spot to calculate the laser damage threshold of the sample.

[0058] The results are shown in Table 1. At 1064 nm, K8Na2Ga 30 S 45 O5,Rb8Na2Ga 30 Se 45 O5,Rb8Na2In 30 Se 45 O5,Cs8Na2In 30 Se 45 Comparison of laser damage thresholds of O5 and AgGaS2 polycrystalline powders, among which K8Na2Ga 30 S 45 O5,Rb8Na2Ga 30 Se 45 O5,Rb8Na2In 30 Se45 O5,Cs8Na2In 30 Se 45 The laser damage threshold of O5 is 43.0, 24.3, 11.4 and 10.0 times that of AgGaS2.

[0059] Table 1

[0060] sample <![CDATA[Laser damage threshold MW / cm 2 > <![CDATA[AgGaS2]]> 2.0 <![CDATA[K8Na2Ga 30 S 45 O5]]> 86.0 <![CDATA[Rb8Na2Ga 30 Yes 45 O5]]> 46.0 <![CDATA[Rb8Na2In 30 Yes 45 O5]]> 22.8 <![CDATA[Cs8Na2In 30 Yes 45 O5]]> 20.0

[0061] Test Example 3

[0062] Crystallographic data tests were performed on Examples 1 to 4, and the results can be summarized as follows:

[0063] K8Na2Ga 30 S 45 O5, belongs to the P-62c space group of the hexagonal system, α=β=90.0°, γ=120.0°,

[0064] Rb8Na2Ga 30 Se 45 O5, belongs to the P-62c space group of the hexagonal system, α=β=90.0°, γ=120.0°,

[0065] Rb8Na2In 30 Se 45 O5, belongs to the P-62c space group of the hexagonal system, α=β=90.0°, γ=120.0°,

[0066] Cs8Na2In 30 Se 45 O5, belongs to the P-62c space group of the hexagonal system, α=β=90.0°, γ=120.0°,

[0067] The above descriptions are merely a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application discloses the preferred embodiments as above, they are not intended to limit the present application. Any technical personnel familiar with the present profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A type of sulfur oxide crystal material, characterized in that: The chemical formula of the sulfur oxide crystal material is A8Na2M 30 Q 45 O5; The sulfur oxide crystal material is K8Na2Ga 30 S 45 O5, belongs to the hexagonal system P -62 c space group, a = b = 11.9Å, c = 7.3 Å, α = β = 90.0︒, γ = 120.0︒, V = 919.2 Å 3 ; The sulfur oxide crystal material is Rb8Na2Ga 30 Se 45 O5, belongs to the hexagonal system P -62 c space group, a = b =12.1 Å, c = 8.1Å, α = β = 90.0︒, γ = 120.0︒, V = 1025.7 Å 3 ; The sulfur oxide crystal material is Rb8Na2In 30 Se 45 O5, belongs to the hexagonal system P -62 c space group, a = b =12.9 Å, c = 9.0 Å, α = β = 90.0︒, γ = 120.0︒, V = 1299.9 Å 3 ; The sulfur oxide crystal material is Cs8Na2In 30 Se 45 O5, belongs to the hexagonal system P -62 c space group, a = b =13.8 Å, c = 9.9 Å, α = β = 90.0︒, γ = 120.0︒, V = 1654.6 Å 3 .

2. The sulfur oxide crystal material according to claim 1, characterized in that: The laser damage threshold of the first type of sulfur oxide crystal material powder is 1 to 50 times that of AgGaS2.

3. The sulfur oxide crystal material according to claim 1, characterized in that: The frequency doubling intensity of the type of oxysulfide crystal material is 0.3 to 5 times that of AgGaS2.

4. The method for preparing a type of sulfur oxide crystal material according to any one of claims 1 to 3, characterized in that: The steps include: A raw material mixture containing element A, element M, element Q, and NaX is placed in a reaction vessel, which is vacuum-sealed and heated to a reaction temperature to react to obtain the aforementioned type of sulfur oxide crystal material; Wherein, X in NaX is selected from at least one of Cl, Br, and I.

5. The preparation method according to claim 4, characterized in that The raw materials containing element A, element M, element Q and NaCl are prepared in a molar ratio of A:M:M2O3:Q:NaX=1:(4-5):(1-2):(6-9):(3-6) and mixed uniformly to obtain the obtained product.

6. The preparation method according to claim 4, characterized in that In the raw material mixture, the source of element A is selected from element A; The source of the M element is selected from at least one of M element and M2O3; The source of the Q element is selected from Q simple substance.

7. The preparation method according to claim 4, characterized in that The reaction conditions are: The reaction temperature is 600°C ~1000°C, and the reaction time is 1 h ~100 h.

8. The preparation method according to claim 4, characterized in that The reaction temperature is reached by heating at a rate of 1°C / h to 60°C / h.

9. The preparation method according to claim 4, characterized in that After the reaction, the temperature needs to be lowered; The cooling is performed by natural cooling or cooling to 300°C to 400°C at a cooling rate of 1°C / h-10°C and then naturally cooling.

10. The preparation method according to claim 4, characterized in that The pressure range of the reaction vessel after vacuuming is 10 -3 Pa -10Pa.

11. Use of the sulfide oxide crystal material according to any one of claims 1 to 3 or the sulfide oxide crystal material obtained by the preparation method according to any one of claims 4 to 10 as a nonlinear optical crystal in the laser field.

Images