CN109137070B - Zn3P2S8Preparation method and application of nonlinear optical crystal - Google Patents

Zn3P2S8Preparation method and application of nonlinear optical crystal Download PDF

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CN109137070B
CN109137070B CN201810295562.1A CN201810295562A CN109137070B CN 109137070 B CN109137070 B CN 109137070B CN 201810295562 A CN201810295562 A CN 201810295562A CN 109137070 B CN109137070 B CN 109137070B
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nonlinear optical
optical crystal
crystal
source material
compound
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CN109137070A (en
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姚吉勇
林哲帅
周墨林
郭扬武
李壮
罗晓宇
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Technical Institute of Physics and Chemistry of CAS
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    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/10—Inorganic compounds or compositions
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B11/00—Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/35—Non-linear optics
    • G02F1/355—Non-linear optics characterised by the materials used
    • G02F1/3551—Crystals

Abstract

The invention discloses Zn3P2S8Preparation method and application of nonlinear optical crystal, and Zn3P2S8The nonlinear optical crystal has no symmetric center, belongs to tetragonal system, and has space group of
Figure DDA0001618638900000011
The unit cell parameters are as follows:α - β -gamma-90 deg. and Z-2. this invention also discloses the method of high temperature spontaneous melt crystallization and Bridgman-Stockbarge method to prepare the nonlinear optical crystal3P2S8The nonlinear optical crystal can be used for manufacturing nonlinear optical devices.

Description

Zn3P2S8Preparation method and application of nonlinear optical crystal
Technical Field
The invention belongs to the field of preparation of nonlinear optical crystals, and particularly relates to Zn3P2S8Non-linear optical crystal (Zn) of3P2S8Single crystal) and the Zn3P2S8Method for producing single crystal and crystal containing the same3P2S8A single crystal nonlinear optical device.
Background
Crystals with nonlinear optical effects are referred to as nonlinear optical crystals. The nonlinear optical effect refers to the effects of frequency doubling, sum frequency, difference frequency, parametric amplification and the like. Only crystals that do not have a center of symmetry may have nonlinear optical effects. By using the nonlinear optical effect of crystal, the nonlinear optical devices such as second harmonic generator, upper and lower frequency converter, optical parametric oscillator, etc. can be made. The laser generated by the laser can be subjected to frequency conversion through the nonlinear optical device, so that more useful wavelengths of laser can be obtained, and the laser can be widely applied. The optical materials can be divided into three categories of nonlinear optical materials in ultraviolet region, visible and near infrared region and middle infrared region according to different application wave bands of the materials. The nonlinear optical crystal materials in the visible light region and the ultraviolet light region can meet the requirements of practical application; the major ones that are practical in the double frequency (532nm) crystal are KTP (KTiOPO)4)、BBO (β-BaB2O4)、LBO(LiB3O5) A crystal; among the frequency tripling (355nm) crystals that are practical are BBO, LBO, CBO (CsB)3O5) And (4) selecting. The development of the nonlinear crystal of the infrared band is slower; most of materials for infrared region are ABC2Type chalcopyrite-structured semiconductor materials, e.g. AgGaQ2(Q ═ S, Se, Te), the optical damage threshold of the infrared nonlinear crystal is too low and the crystal growth is difficult, directly affecting practical use. The mid-infrared band nonlinear optical crystal has important application in the field of photoelectron, for example, it can extend the laser (such as 1.064 μm) of near-infrared band to the mid-infrared region by means of optical parametric oscillation or optical parametric amplification; it can also be used for the middle infrared region (such as CO)2Laser, 10.6 μm) is frequency doubled, which is of great significance for obtaining laser with continuously adjustable wavelength. Therefore, the search for new infrared nonlinear optical crystal materials with excellent performance has become a difficult problem in the current research field of nonlinear optical materialsOne of a point and a leading direction.
Disclosure of Invention
The invention aims to provide Zn3P2S8A preparation method of nonlinear optical crystal. It is still another object of the present invention to provide Zn3P2S8Use of a nonlinear optical crystal.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides Zn3P2S8A nonlinear optical crystal of said Zn3P2S8The nonlinear optical crystal has no symmetric center, belongs to tetragonal system, and has space group of
Figure BDA0001618638880000023
The unit cell parameters are as follows:
Figure BDA0001618638880000021
Figure BDA0001618638880000022
α＝β＝γ＝90，Z＝2。
the invention also provides a method for preparing the Zn3P2S8Method for growing a non-linear optical crystal by high temperature melt spontaneous crystallization3P2S8A nonlinear optical crystal comprising the steps of:
will have a composition equivalent to Zn3P2S8Mixture or powder of Zn3P2S8Heating the compound to melt to obtain high-temperature melt, keeping the high-temperature melt for 24-96 hours, and then cooling to room temperature at the cooling rate of 1-10 ℃/hour to obtain Zn3P2S8A nonlinear optical crystal.
Preferably, the composition is equivalent to Zn3P2S8The mixture of (1) comprises a Zn source material and a P source material; the Zn source material is Zn or ZnS; the P source material is P or P2S5。
Further preferred areThe composition is equivalent to Zn3P2S8The mixture of (1) further comprises elemental S.
The invention also provides another method for preparing the Zn3P2S8Method for growing Zn by crucible descending method3P2S8The nonlinear optical crystal specifically comprises the following steps:
will have a composition equivalent to Zn3P2S8Mixture or powder of Zn3P2S8Placing the compound in a crystal growth device, slowly heating until the raw materials are molten, after the raw materials are completely molten, vertically descending the crystal growth device at a speed of 0.1-10mm/h, and carrying out Zn in the descending process of the crystal growth device3P2S8The nonlinear optical crystal grows in a growth period of 5-20 days.
Preferably, the composition is equivalent to Zn3P2S8The mixture of (1) comprises a Zn source material and a P source material; the Zn source material is Zn or ZnS; the P source material is P or P2S5。
Further preferably, the equivalent is Zn3P2S8The mixture of (1) further comprises elemental S.
For preparing said Zn3P2S8The crystals may be powdered Zn3P2S8Said powdered Zn3P2S8The preparation process of the compound comprises the following steps:
uniformly mixing a Zn source material, a P source material and a simple substance S according to the molar ratio of Zn to P to S of 3 to 2 to 8, and heating to 350-550 ℃ for solid-phase reaction (in principle, the general chemical synthesis method can be adopted to prepare Zn3P2S8A compound; the solid phase reaction method is preferred in the invention) to obtain Zn with the chemical formula3P2S8Is crushed and ground to obtain powdered Zn3P2S8A compound of (1);
the Zn source material may be Zn or ZnS;
the P source material can be P or P2S5。
Said Zn3P2S8The compound can be prepared according to the following chemical reaction formula:
(1)3Zn+2P+8S＝Zn3P2S8；
(2)3ZnS+2P+5S＝Zn3P2S8；
(3)3Zn+P2S5+3S＝Zn3P2S8；
(4)3ZnS+P2S5＝Zn3P2S8。
zn with centimeter-level size can be obtained by adopting the two methods3P2S8A nonlinear optical crystal; by using large-sized crucibles and extending the growth period, a correspondingly larger size of Zn can be obtained3P2S8A nonlinear optical crystal.
According to the crystallographic data of crystal, the crystal blank is oriented, the crystal is cut according to the required angle, thickness and section size, the light-passing surface of the crystal is polished, and the crystal can be used as a nonlinear optical device, and the Zn3P2S8The nonlinear optical crystal has the advantages of large nonlinear optical effect, wide light transmission range, stable physical and chemical properties, higher hardness, good mechanical properties, difficult cracking, easy processing and storage and the like.
The invention still further provides a nonlinear optical device comprising the Zn3P2S8A nonlinear optical crystal. Zn3P2S8The nonlinear optical crystal can be used for preparing a nonlinear optical device comprising passing at least one beam of incident electromagnetic radiation through at least one piece of Zn3P2S8Means for generating at least one output radiation having a frequency different from that of the incident electromagnetic radiation after the nonlinear optical crystal.
Preparation of Zn according to the invention3P2S8The crystal is easy to grow in the growth process of the nonlinear optical crystal, is transparent and free of package, and has growth effectThe speed is high, the cost is low, crystals with larger size can be easily obtained, and the like; zn obtained3P2S8The nonlinear optical crystal has the advantages of large nonlinear optical effect, wide light-transmitting wave band, high hardness, good mechanical property, difficult cracking and deliquescence, easy processing and storage and the like; the Zn is3P2S8The nonlinear optical crystal can be used for manufacturing nonlinear optical devices.
Drawings
FIG. 1 is a Zn in accordance with the present invention3P2S8Working principle diagram of a typical nonlinear optical device made of nonlinear optical crystal, wherein 1 is laser, 2 is incident laser beam, and 3 is Zn after crystal post-treatment and optical processing3P2S8A nonlinear optical crystal, 4 is the generated outgoing laser beam, and 5 is a filter.
FIG. 2 is Zn3P2S8The structure of the nonlinear optical crystal is shown schematically.
Detailed Description
Any feature disclosed in this specification may be replaced by alternative features serving equivalent or similar purposes, unless expressly stated otherwise. Unless expressly stated otherwise, each feature is only an example of a generic series of equivalent or similar features. The description is only for the purpose of facilitating understanding of the present invention and should not be construed as specifically limiting the present invention.
The invention is described in further detail below with reference to the figures and the detailed description.
Example 1: preparation of Zn by high-temperature melt spontaneous crystallization method3P2S8Crystal:
5.846 g ZnS and 4.445 g P were weighed out2S5(i.e., ZnS: P)2S50.06mol:0.02mol), mixing, placing into a quartz glass tube with diameter of 12mm × 200mm, and vacuumizing to 10%-3Packaging with oxyhydrogen flame, placing in a tubular growth furnace, slowly heating to 650 ℃, keeping the temperature for 96 hours, slowly cooling to room temperature at the speed of 1 ℃/h, and closing the tubular growth furnace; cutting the quartz tube after cooling to obtain phi20x60mm white Zn3P2S8And (4) crystals.
Example 2: preparation of Zn by Bridgman method3P2S8Crystal:
11.692 g ZnS and 8.890 g P were weighed out2S5(Zn: P: S: 0.12mol:0.08mol:0.32mol), uniformly mixed, put into a quartz glass tube of phi 25 mm. times.200 mm, and evacuated to 10mm-3Packaging with oxyhydrogen flame, placing in a crystal growth furnace, slowly heating to 650 deg.C to melt the raw materials, and vertically descending the growth device at a speed of 0.1-10 mm/hr after the raw materials are completely melted; after the crystal growth is finished, the growing device is cooled to the room temperature for 50 hours to obtain phi 30x90mm white Zn3P2S8And (4) crystals.
Tested, Zn prepared in example 1-2 above3P2S8The nonlinear optical crystal belongs to the tetragonal system and has a space group of
Figure BDA0001618638880000041
The unit cell parameters are as follows:
Figure BDA0001618638880000042
°
α＝β＝γ＝90，Z ＝2。
Figure BDA0001618638880000043
has frequency doubling effect, and the light transmission range is 1-20 μm; FIG. 2 shows the Zn3P2S8The structure of the nonlinear optical crystal is shown schematically.
Example 3:
zn obtained in example 1-23P2S8The crystal is not easy to be broken and deliquesced, and is easy to be cut, polished and stored. Zn obtained in example 1-23P2S8A crystal placed at the position 3 of the device shown in figure 1, using Q-switched Ho: Tm: Cr: YAG laser as light source at room temperature, and inputting infrared light with wavelength of 2090nm and outputting frequency-doubled light with wavelength of 1045nm, wherein the laser intensity is AgGaS under the same condition22.6 times of the total weight of the powder.
FIG. 1 is a Zn film using the present invention3P2S8Working principle diagram of a typical nonlinear optical device made of nonlinear optical crystal, wherein 1 is laser, 2 is incident laser beam, and 3 is Zn after crystal post-treatment and optical processing3P2S8A nonlinear optical crystal 4 is the generated outgoing laser beam, and 5 is a filter; an incident laser beam 2 emitted by a laser 1 is incident on Zn3P2S8The single crystal 3 generates an outgoing laser beam 4 which is passed through a filter 5 to obtain the desired laser beam.
Using Zn of the invention3P2S8The device made of the nonlinear optical crystal can be a frequency doubling generator, an upper frequency converter, a lower frequency converter and an optical parametric oscillator. Optical parametric amplifiers, and the like.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims.

Claims (6)

1. Zn3P2S8A method for producing a nonlinear optical crystal, the method comprising the steps of:
zn growth by high-temperature melt spontaneous crystallization method or Bridgman method3P2S8A nonlinear optical crystal;
the high-temperature melt spontaneous crystallization method is used for growing Zn3P2S8The nonlinear optical crystal comprises the following steps:
will have a composition equivalent to Zn3P2S8Mixture or powder of Zn3P2S8Heating the compound to melt to obtain high-temperature melt, keeping the high-temperature melt for 24-96 hours, and then cooling to room temperature at the cooling rate of 1-10 ℃/hour to obtain Zn3P2S8Non-linearityAn optical crystal;
the Bridgman method is used for growing Zn3P2S8The nonlinear optical crystal comprises the following steps:
will have a composition equivalent to Zn3P2S8Mixture or powder of Zn3P2S8Placing the compound in a crystal growth device, slowly heating until the raw materials are molten, after the raw materials are completely molten, vertically descending the crystal growth device at a speed of 0.1-10mm/h, and carrying out Zn in the descending process of the crystal growth device3P2S8The nonlinear optical crystal grows in a growth period of 5-20 days.
2. Zn according to claim 13P2S8A method for producing a nonlinear optical crystal, characterized in that the composition is equivalent to Zn3P2S8The mixture of (1) comprises a Zn source material, a P source material and a simple substance S;
the Zn source material is Zn or ZnS;
the P source material is P or P2S5。
3. Zn according to claim 13P2S8A method for producing a nonlinear optical crystal, characterized in that the Zn is in a powdery form3P2S8The preparation method of the compound comprises the following steps:
uniformly mixing a Zn source material, a P source material and a simple substance S according to the molar ratio of Zn to P to S of 3 to 2 to 8, heating to 350-550 ℃ for reaction to obtain Zn with the chemical formula3P2S8Is crushed and ground to obtain powdered Zn3P2S8The compound of (1).
4. Zn according to claim 33P2S8The preparation method of the nonlinear optical crystal is characterized in that the Zn source material is Zn or ZnS; the P source material is P or P2S5。
5. Zn produced by the production method described in any one of claims 1 to 43P2S8The application of the nonlinear optical crystal in preparing a nonlinear optical device.
6. A nonlinear optical device comprising Zn prepared by the method of any one of claims 1 to 43P2S8A nonlinear optical crystal.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2650501B2 (en) * 1990-06-12 1997-09-03 宇部興産株式会社 Nonlinear optical material
CN101235542A (en) * 2007-11-14 2008-08-06 哈尔滨工业大学 Polycrystalline synthesis and single-crystal growth method for germanium zinc phosphide
CN105543971A (en) * 2016-02-04 2016-05-04 中国科学院理化技术研究所 AgZnPS4 nonlinear optical crystal, and preparation method and nonlinear optical device thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2650501B2 (en) * 1990-06-12 1997-09-03 宇部興産株式会社 Nonlinear optical material
CN101235542A (en) * 2007-11-14 2008-08-06 哈尔滨工业大学 Polycrystalline synthesis and single-crystal growth method for germanium zinc phosphide
CN105543971A (en) * 2016-02-04 2016-05-04 中国科学院理化技术研究所 AgZnPS4 nonlinear optical crystal, and preparation method and nonlinear optical device thereof

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Stefan Jörgens等.Motive dichtester Kugelpackungen: Die Verbindungen Zn3(PS4)2 und LiZnPS4.《Z. Anorg. Allg. Chem.》.2002,第628卷1765-1769. *
SynthesisandgrowthofZnGeP2 crystals: Preventionofnon-stoichiometry;Jiang Cheng等;《Journal ofCrystalGrowth》;20130101;第362卷;125-129 *
新型硫族化合物在中红外非线性光学晶体方面研究进展;尹文龙等;《强激光与粒子束》;20140715;第26卷(第7期);071009 *

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