CN1737217A

CN1737217A - Non-linear optics crystal material, process for preparing the same and purposes thereof

Info

Publication number: CN1737217A
Application number: CN 200510019301
Authority: CN
Inventors: 苏旭; 刘涛; 秦金贵; 张刚; 陈创天; 吴以成
Original assignee: Wuhan University WHU
Current assignee: Wuhan University WHU
Priority date: 2005-08-16
Filing date: 2005-08-16
Publication date: 2006-02-22
Anticipated expiration: 2025-08-16
Also published as: CN100362145C

Abstract

The invention discloses a non-linear optical crystal material having a general formula of HgaObSO4, wherein a=2-3, b=1-2. The preparation process comprises the following steps, grinding HgO and HgSO4 by the mol ratio of 2:1 or 1:1, loading into an ampere tube, vacuum-pumping the ampere tube to below 0.1Pa, sealing the tube, placing into a Muffle furnace, reacting more than 100 hours at 500-540 deg. C.

Description

Nonlinear optical crystal material and preparation method and application thereof

Technical Field

The invention relates to an inorganic nonlinear optical crystal material, a preparation method and application thereof, belonging to the field of inorganic chemistry and also belonging to the field of optical materials.

Background

For inorganic substances, KDP (potassium dihydrogen phosphate), KTP (potassium titanyl phosphate), BBO (β -barium metaborate), LBO (lithium borate), AgGaSe have been discovered over the past three decades₂、ZnGeP₂And the like. The research is mainly developed from two aspects, namely, a crystal which is more perfect and meets the application requirements better is grown from a known nonlinear optical (NLO) material through a crystal growth technology; the second is to find new nonlinear optical materials, which includes synthesizing new compounds and finding materials with good nonlinear optical properties from known compounds. Classical frequency doubling materials in the visible region are KTP and KDP, which contain distorted [ PO]in their structure₄]、[MO₄]The groups and the distorted arrangement are basically consistent and macroscopically strengthened mutually, thereby generating larger SHG effect. The sulfate often contains [ SO]₄]And [ MO₄]Groups, if distorted and superimposed on each other, may produce large nonlinear effects. In the seventies of the twentieth century, studies on nonlinear optical properties of sulfates, such as NH, began₄LiSO₄，NH₄NaSO₄·2H₂O，KLiSO₄，(NH₄)₂SO₄Etc.; however, so far, only BeSO₄·4H₂O is considered a potentially useful nonlinear optical material. BeSO₄·4H₂O belongs to-42 m point group and the frequency multiplication coefficient is d₃₆(0.5321μm)＝0.62×d₃₆KDP, light transmission range is 0.17-1.5821 μm.

The invention content is as follows:

the invention aims to provide an inorganic nonlinear optical crystal material which has a larger bandwidth, a larger laser damage threshold and a wider light transmission range.

The technical scheme provided by the invention is as follows: a nonlinear optical crystal material has a general formula: HgaO_bSO₄Wherein when a is 2, b is 1; when a is 3, b is 2.

The preparation method of the nonlinear optical crystal material comprises the following steps:

Hg₃O₂SO₄: mixing HgO and HgSO in a molar ratio of 2: 1₄Grinding uniformly, and putting into an incubator tube; then vacuumizing the ampoule tube to below 0.1Pa, and sealing the ampoule tube; putting the mixture into a muffle furnace, and reacting for more than 100 hours at 500-540 ℃ to obtain a large amount of orange crystal powder. The following is the preparation of the compound Hg of the invention₃O₂SO₄The reaction equation of (1):

Hg₂OSO₄: mixingHgO and HgSO in a molar ratio of 1: 1₄Grinding uniformly, and vacuumizing the ampoule tube to 0.1Sealing the pipe below Pa; putting the mixture into a muffle furnace, and reacting for more than 100 hours at 500-540 ℃ to obtain a large amount of light yellow crystalline powder. The following is the preparation of the compound Hg of the invention₂OSO₄The reaction equation of (1):

the sulfate is one of the most commonly used materials and is cheap, so the sulfate with the nonlinear effect has wide market prospect when being used as a frequency doubling material.

The inorganic nonlinear optical material disclosed by the invention is completely transparent in a visible light region, wherein the light transmission range of an infrared region reaches 7.2 mu m; the ultraviolet absorption edges were 0.5 and 0.2 μm, respectively. They all have higher nonlinear optical coefficient and better other physical and chemical properties, and can be applied as nonlinear optical materials.

The novel inorganic infrared nonlinear optical crystal material prepared by the invention has the following characteristics:

1. has larger frequency doubling effect (SHG), and the Kurtz powder frequency doubling test result shows that the SHG: hg is a mercury vapor₂OSO₄: 0.8 times KTP; hg is a mercury vapor₃O₂SO₄: it is 0.6 times KTP.

2. The compound has wide transparent ranges in ultraviolet, visible light regions and infrared light regions, and the completely transparent regions are respectively as follows: hg is a mercury vapor₂OSO₄：0.2-7.2μm；Hg₃O₂SO₄：0.5-7.2μm。

3.The fact that the visible light region is transparent means that the bandwidth of the compound is large, and the laser damage threshold of the crystal is large; the calculated energy gap values of the compounds are respectively as follows: hg is a mercury vapor₂OSO₄：6.2eV；Hg₃O₂S₄：2.8eV。

4. Does not contain crystal water, is stable to air, does not deliquesce, and has good thermal stability, and the thermal decomposition temperature is respectively as follows: hg is a mercury vapor₂OSO₄：500℃；Hg₃O₂SO₄：450℃。

Drawings

FIG. 1 is Hg of the present invention₂OSO₄An XRD pattern of (a);

FIG. 2 is Hg of the present invention₂OSO₄Transmitting the spectrum in the ultraviolet-visible-near infrared band;

FIG. 3 is Hg of the present invention₂OSO₄The infrared band transmission spectrum of (1); wherein the peaks are labeled as water adsorbed by KBr in the pellet;

FIG. 4 is Hg of the present invention₃O₂SO₄An XRD pattern of (a);

FIG. 5 is Hg of the present invention₃O₂SO₄Transmitting the spectrum in the ultraviolet-visible-near infrared band;

FIG. 6 is Hg of the present invention₃O₂SO₄The infrared band transmission spectrum of (1); where the peaks are indicated as water adsorbed by KBr in the pellet.

Detailed Description

The technical solution of the present invention is further described with reference to the following specific examples:

example 1: hg is a mercury vapor₂OSO₄Preparation of

1.083g (50mmol) HgO and 1.483g (50mmol) HgSO₄Grinding uniformly in an agate grinding bowl, and putting into a quartz incubator tube; vacuumizing to below 1.0Pa, and sealing the tube with H-O flame; then placing into a muffle furnace, and burning at 520 DEG CAfter 120 hours, a large amount of orange-colored crystalline powder can be obtained.

Example 2: hg is a mercury vapor₃O₂SO₄Preparation of

2.166g (100mmol) of HgO and 1.483g (50mmol) of HgSO₄Grinding uniformly in an agate grinding bowl, and putting into a quartz incubator tube; vacuumizing to below 1.0Pa, and sealing the tube with H-O flame; then placing the mixture into a muffle furnace, and sintering the mixture for 120 hours at 520 ℃ to obtain a large amount of light yellow crystalline powder.

The obtained product is examined by X-ray powder diffraction. And the physicochemical properties of the materials are detected by infrared, ultraviolet-visible-near infrared and thermogravimetric analysis.

Example 3: hg is a mercury vapor₂OSO₄Frequency doubling effect of single crystal powder

Hg is treated₂OSO₄Grinding the crystal, and putting the crystal into a metal sample cell with a symmetrical glass window; the KTP in the same state is used as a reference, 1064nm laser generated by an Nd: YAG laser is used as a light source for testing, and the obtained signal is displayed on an oscilloscope. Hg is a mercury vapor₂OSO₄The crystal powder produced a frequency doubling signal of 0.8 times the size of KTP. The compoundcan be used as a second-order nonlinear optical material, and can generate a frequency doubling effect on laser in a light transmission range.

Example 4: hg is a mercury vapor₃O₂SO₄Frequency doubling effect of single crystal powder

Hg is treated₃O₂SO₄Grinding the crystal, and putting the crystal into a metal sample cell with a symmetrical glass window; using KDP in the same state as reference, Nd: YAAnd the 1064nm laser generated by the G laser is used as a light source for testing, and the obtained signal is displayed on an oscilloscope. Hg is a mercury vapor₃O₂SO₄The crystal powder produced a frequency doubling signal of 0.6 times the size of KTP. The compound can be used as a second-order nonlinear optical material, and can generate a frequency doubling effect on laser in a light transmission range.

Example 5: hg is a mercury vapor₂OSO₄Application as second-order nonlinear material

Hg to be prepared₂OSO₄The particle crystal is placed in a glass sample cell and placed on the laser light path, then a beam of red laser light (wavelength 1064nm) is made to enter the sample cell, the sample produces green light (wavelength 532rm), the wavelength of the produced light is exactly twice the wavelength of the incident laser light, i.e. HgSO₄The crystal doubles the frequency of the incident laser light.

Example 6: hg is a mercury vapor₃O₂SO₄Application as second-order nonlinear material

Hg to be prepared₃O₂SO₄The particle crystal is placed in a glass sample cell and placed on the laser light path, then a beam of red laser light (wavelength 1064nm) is made to enter the sample cell, the sample produces green light (wavelength 532nm), the wavelength of the produced light is just twice of the incident laser wavelength, i.e. HgSO₄The crystal doubles the frequency of the incident laser light.

FIG. 1 and FIG. 4 are respectively the material Hg₂OSO₄And Hg₃O₂SO₄X-ray powder diffraction pattern of (1), HgO, HgSO₄The characteristic diffraction peak disappears, which indicates that a new phase is generated, the baseline of the diffraction peak is very stable, the peak shape is sharp, and the crystal form of the product is better. As can be seen from FIGS. 2 and 5, Hg₂OSO₄And Hg₃O₂SO₄The ultraviolet absorption edges of the film are 200 nm and 500 nm in sequence, and the film does not absorb in a visible light region and a near infrared light region (to 2500 nm); from the infrared absorption spectrum visible (FIGS. 3, 6), Hg₂OSO₄And Hg₃O₂SO₄There was a small absorption peak at 1384.3 and 1384.0 wavenumbers respectively,the characteristic absorption of the S-O bond occurs at around 1110 wave numbers; byHg can be judged by the above analysis₂OSO₄And Hg₃O₂SO₄The light transmission ranges of (a) and (b) are 0.2-7.2 and 0.5-7.2 μm, respectively. Partial electronic information of molecules can be obtained from the spectral information, and energy gaps of the compounds can be estimated according to ultraviolet absorption edges of the compounds, wherein the energy gaps are respectively as follows: hg is a mercury vapor₂OSO₄：6.2eV；Hg₃O₂SO₄: 2.8 eV. According to the frequency doubling test result of the compound, the compound can be used as a second-order nonlinear optical material and can generate a frequency doubling effect on laser in a light transmission range. Therefore, Hg₂OSO₄And Hg₃O₂SO₄Can generate frequency doubling effect on laser within the wavelength ranges of 0.2-7.2 and 0.5-7.2 μm respectively.

Claims

1. A nonlinear optical crystal material has a general formula: hg is a mercury vapor_aO_bSO₄Wherein when a is 2, b is 1; when a is 3, b is 2.

2. A method for preparing a nonlinear optical crystalline material in accordance with claim 1, wherein: mixing HgO and HgSO in a molar ratio of 2: 1 or 1: 1₄Grinding uniformly, and putting into an incubator tube; then vacuumizing the ampoule tube to below 0.1Pa, and sealing the ampoule tube; and (3) placing the mixture into a muffle furnace, and reacting for more than 100 hours at 500-540 ℃ to obtain the nonlinear optical crystal material.

3. Use of the nonlinear optical crystal material in claim 1 in the optical field.

4. Use according to claim 3, characterized in that: the crystal material is applied to laser frequency doubling in a wave band of 0.5-7.2 μm or 0.2-7.2 μm respectively.