CN101323981B - Use of birefraction borate crystal - Google Patents
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- CN101323981B CN101323981B CN 200810084388 CN200810084388A CN101323981B CN 101323981 B CN101323981 B CN 101323981B CN 200810084388 CN200810084388 CN 200810084388 CN 200810084388 A CN200810084388 A CN 200810084388A CN 101323981 B CN101323981 B CN 101323981B
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Abstract
The invention relates to an optical borate-series crystal with double refraction and application thereof. The borate-series crystal with double refraction has the chemical formula of ReBa3B9O18 (Re equals to Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu). The crystals are all uniaxial negative crystals, which have the birefringence of about 0.08 to 0.15 in the visible light band. The crystals in the series are easy to be incised, ground, polished and stored, are water immiscible, non-deliquescent and stable in air, and are suitable for being used for producing optical communication elements such as optoisolators, circulators, light beam shifters, optical polarizers and optical modulators, etc., in particular for producing polarizing prisms, phase delaying devices and electro-optical modulators with various purposes. The devices utilize the refraction index property of the optical borate-series crystal, particularly the larger birefringence (ne-no) thereof.
Description
Technical field
The present invention relates to double refraction optics field of crystals, particularly relate to a kind of borate-based ReBa
3B
9O
18The birefringece crystal of (Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu) and uses thereof.
Background technology
Birefringent phenomenon is one of key character of showing when propagating in photosensitiveness heterogeneous body crystal of light.When light is propagated in photosensitiveness heterogeneous body (as: crystal beyond the isometric system), except indivedual special directions (along optical axis direction), can change its vibration characteristic, it is orthogonal to be decomposed into two electric vector direction of vibration, velocity of propagation is different, the two bundle polarized light that specific refractory power does not wait, this phenomenon is called double refraction, and such crystal is called birefringece crystal.A branch of in the two-beam observes general the law of refraction, is called ordinary light (o light), its specific refractory power n
oExpression, another bundle is not observed general the law of refraction, is called non-ordinary light (e light), its specific refractory power n
eExpression.Utilize the characteristic of birefringece crystal can obtain line polarized light, realize the displacement of light beam etc.Thereby so that birefringece crystal becomes the making optoisolator, circulator, pattern displacement device, the sealed cell critical materials such as optical polariser and optical modulator.
Birefringent material commonly used mainly contains calcite, rutile, LiNbO
3, YVO
4And α-BaB
2O
4Crystal etc.Yet calcite crystal mainly exists with natural form, and synthetic is difficulty relatively, and stock size is all smaller, and foreign matter content is higher, can't satisfy the requirement of large size optics polarization element, and is easy to cleavage, and processing is difficulty relatively, and the crystal utilization ratio is low.Rutile also mainly exists with natural form, and synthetic is difficulty relatively, and size is less, and hardness is large, is difficult to processing.LiNbO
3Crystal is easy to obtain large-size crystals, but degree of birefringence is too little.YVO
4A kind of well behaved synthetic birefringence crystal, but because YVO
4Fusing point is high, must use iridium crucible to carry out the crystal growth, and growth atmosphere is weak oxygen atmosphere, thereby has the problem of appraising at the current rate of v element when growth, and so that crystal mass descends the also high-quality crystal of difficult acquisition.α-BaB
2O
4Owing to have solid-state phase changes, be easy in crystal growing process, ftracture.Given this, be necessary very much to seek a kind of growth, stable in properties and birefringece crystal with larger degree of birefringence of being easy to.The borate compound that Inst. of Physics, CAS's crystal growth group was reported a series of isomorphisms in 2004 is consulted document 1:Li, X.Z.; Wang, C.; Chen, X.L.; Li, H.; Jia, L.S.; Wu, L.; Du Y.X.; Xu, Y.P.Inorg.Chem.2004,43,8555.The chemical formula of this series compound is ReBa
3B
9O
18(Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu).Their spacer all is P6
3/ m, basic structural unit are the B that is arranged in parallel along c-axis
3O
6The plane group, this plane group might cause large degree of birefringence.That but the specific refractory power of accurately measuring crystal needs is larger-size, optical quality monocrystalline preferably.And above-mentioned document has just synthesized powdered sample, does not obtain valuable crystal prototype.Therefore, at present, obtain the borate-based ReBa of monocrystalline
3B
9O
18It is the technical problem that needs to be resolved hurrily that the birefringece crystal of (Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu) comes its degree of birefringence measurement.
Summary of the invention
In order to overcome above-mentioned technical problem, one of purpose of the present invention provides a kind of ReBa
3B
9O
18The double refraction borate crystal that (Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu) is borate-based.
Another object of the present invention provides a kind of purposes of above-mentioned crystal.
To achieve these goals, the present invention has adopted following technical scheme:
The invention provides a kind of ReBa
3B
9O
18(Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu) borate-based birefringece crystal, preferred monocrystalline, wherein, this crystal is transparent and be uniaxial negative crystal n
e<n
oDegree of birefringence (the n of crystal
e-n
o) numerical values recited is about 0.08-0.15; This crystal is easy to processing and preserves, and water insoluble, and deliquescence is not stable in the air, is applicable to make.
Wherein, preferred ReBa
3B
9O
18(Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu) borate-based birefringece crystal size is not less than 1 * 1 * 0.5mm
3, more preferably 6 * 6 * 3~12 * 12 * 7mm
3
The invention provides a kind of ReBa
3B
9O
18The purposes of the birefringece crystal that (Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu) is borate-based, described borate-based birefringece crystal can be used for making light communication element, such as optoisolator, circulator, pattern displacement device, optical polariser and optical modulator etc.Especially for making ahrens prism, phase delay device and electro-optical modulation device etc.These devices use be the refractive index characteristic of crystal, larger degree of birefringence (n particularly
e-n
o), this crystal is 0.10-0.12 in the degree of birefringence size of visible light wave range.
ReBa of the present invention
3B
9O
18(Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu) borate-based birefringece crystal, can carry out single crystal growing with the high-temperature fusant method, and have following character: crystal is transparent; Crystal is uniaxial negative crystal n
e<n
oDegree of birefringence (the n of crystal
e-n
o) numerical values recited is about 0.08-0.15.This crystal is easy to cutting, grinds, polishes and preserves simultaneously, and water insoluble, deliquescence is not stable in the air, so be very suitable for making above-mentioned optics.
Description of drawings
Accompanying drawing 1 is ErBa
3B
9O
18The prism of crystal;
Accompanying drawing 2 is YBa
3B
9O
18The prism of crystal;
Accompanying drawing 3 is ErBa under the different wave length
3B
9O
18The specific refractory power of crystal;
Accompanying drawing 4 is ErBa
3B
9O
18The value of each coefficient in the crystalline dispersion equation;
Accompanying drawing 5 is YBa under the different wave length
3B
9O
18The specific refractory power of crystal;
Accompanying drawing 6 is YBa
3B
9O
18The value of each coefficient in the crystalline dispersion equation;
Accompanying drawing 7 is birefringent wedge crystal polarization beam apparatus synoptic diagram;
Accompanying drawing 8 is the optoisolator synoptic diagram;
Accompanying drawing 9 is pattern displacement device synoptic diagram.
Embodiment
At first, ReBa
3B
9O
18The growth of the double refraction monocrystalline that (Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu) is borate-based adopts melting method to carry out, and this sentences the YBa that grows
3B
9O
18And ErBa
3B
9O
18Two kinds of crystal are that example is explained, and its concrete growth method can be consulted Chinese patent " a kind of preparation method of scintillation crystal barium yttrium borate and the purposes " (application number: 200710063683.5) in having applied for.By the method for this patent, can prepare the ReBa of different rare earth elements
3B
9O
18The double refraction monocrystalline that (Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu) is borate-based, just growth temperature changes to some extent with the change of element, repeats no more the concrete process of growth of different elements here.Such as, ErBa
3B
9O
18The growth method of crystal and YBa
3B
9O
18Crystal is basic identical, and that different is ErBa
3B
9O
18Fusing point be 1039 ℃, other growth parameter(s) then with YBa
3B
9O
18Crystal is similar.Specific refractory power to monocrystalline has adopted prism method to measure, and its basic skills is consulted State Standard of the People's Republic of China's " test method of crystal refractive index " (GB/T 16863-1997).Wherein, respectively with refraction index test sample ErBa
3B
9O
18Crystal and YBa
3B
9O
18Crystal is made prism as depicted in figs. 1 and 2, because crystal is thinner, they are combined with one or two glass cements respectively and grind and polishing.The rib of prism is optical axis [001] direction that is parallel to crystal.Fig. 1 is ErBa
3B
9O
18The prism of crystal, the prism angle of utilizing goniometer to measure crystal is 30 ° 10 ' 25 ".Fig. 2 is YBa
3B
9O
18The prism of crystal, the prism angle of utilizing goniometer to measure crystal is 17 ° 20 ' 44 ".Wherein end face ABC is perpendicular to the direction of optical axis, and two logical light faces of prism are respectively perpendicular to end face and all optical grade polishings.Face AA ' B ' B is the plane of incidence of light, and face AA ' C ' C is exit facet.YBa
3B
9O
18And ErBa
3B
9O
18Equally all be uniaxial negative crystal, their specific refractory poweres under same incident wavelength are very close, as: 4358
During incident wavelength, ErBa
3B
9O
18E light and the specific refractory power of o light be respectively: 1.6059 and 1.7327, and YBa
3B
9O
18The value that crystal is corresponding is 1.6014 and 1.7224, can find out that the difference of specific refractory power of these two kinds of crystal is very little, and degree of birefringence is also very close, all at 0.10-0.12.Because the B in this specific character of specific refractory power and the crystal
3O
6Anionic group is relevant, and is very little with its rare earth ion relation, can reason out thus the series compound ReBa of this isomorphism
3B
9O
18Other compound also should be the uniaxial negative crystal with larger degree of birefringence in (Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu).
Embodiment 1 ErBa
3B
9O
18The crystal refractive index test
Fig. 3 has listed the refraction index test result from purple light to 8 different wave lengths of red visible scope.Test result shows, ErBa
3B
9O
18Crystal is brilliant for negative single shaft, and its degree of birefringence is about-0.11 in visible wavelength range.(404.7nm) specific refractory power of purple light ordinary light is 1.7327, and (656.3nm) specific refractory power of ruddiness ordinary light is 1.7059, its dispersion n
Purple-n
Red=0.0268.
ErBa
3B
9O
18Specific refractory power-the dispersion equation of crystal can be expressed by the Sellmeier equation of four parameters:
In the formula λ represent the vacuum medium wavelength (
), n is specific refractory power, each Coefficient Fitting result is as shown in Figure 4 in the following formula when 295K.Utilize this equation in certain wavelength region, to calculate refractive index value.
Fig. 5 has listed the refraction index test result from purple light to 8 different wave lengths of red visible scope.Test result shows, YBa
3B
9O
18Crystal is brilliant for negative single shaft, and its degree of birefringence is about-0.12 in visible wavelength range.(404.7nm) specific refractory power of purple light ordinary light is 1.7291, and (656.3nm) specific refractory power of ruddiness ordinary light is 1.7000, its dispersion n
Purple-n
Red=0.0291.
YBa
3B
9O
18Specific refractory power-the dispersion equation of crystal: the Sellmeier equation of four parameters
In the formula λ represent the vacuum medium wavelength (
), n is specific refractory power, each Coefficient Fitting result is as shown in Figure 6 in the following formula when 295K.Utilize this equation in certain wavelength region, to calculate refractive index value.
These a series of boratory large specific refractory poweres come from its group B
3O
6Optical anisotropy.B
3O
6By 3 BO
3Group consists of, and BO
3Group is parallel to the plane under the effect of external electric field very different with the polarization perpendicular to the plane.And according to the Wooster rule, the crystal of all laminate structures if do not contain the OH group, all is negative optical axis crystal, consults document [Wooster, W.A.1931, Zeit.Krist., 80,495-503].Utilize Bragg about the Theoretical Calculation of specific refractory power, consult [Ye Danian, structure optical mineralogy, Geology Publishing House, 1998] and can calculate NdBa
3B
9O
18Crystal refractive index, n
eIn the 1.58-1.62 scope, n
oIn the 1.70-1.73 scope, be still uniaxial negative crystal, degree of birefringence is in the 0.1-0.13 scope.
Embodiment 4 TbBa
3B
9O
18The calculating of crystal refractive index
These a series of boratory large specific refractory poweres come from its group B
3O
6Optical anisotropy.B
3O
6By 3 BO
3Group consists of, and BO
3Group is parallel to the plane under the effect of external electric field very different with the polarization perpendicular to the plane, are similar to CO
3Group.Utilize Bragg about the Theoretical Calculation of specific refractory power, consult [Ye Danian, structure optical mineralogy, Geology Publishing House, 1998] and can calculate TbBa
3B
9O
18Crystal refractive index, n
eIn the 1.57-1.62 scope, n
oIn the 1.69-1.73 scope, be still uniaxial negative crystal, the degree of birefringence numerical values recited is the 0.1-0.14 scope.
Application Example 1
Birefringent wedge crystal polarization beam apparatus, as shown in Figure 7, the birefringece crystal of a wedge type, the orientation of optical axis is as shown in Figure 7.Can be divided into two bunch polarized light through crystal after a branch of natural light incident.Degree of birefringence is larger, and two-beam can separate far, is convenient to the separation of light beam.
Application Example 2
Optoisolator, faraday's optical rotator that incoming beam polarization plane rotation 45 is spent can be placed one a pair of 45 degree that are each other to intersect between the birefringece crystal polarizer of placing, then can consist of an optoisolator, it only allows the light beam of forward-propagating by this system, and the light beam of backpropagation is blocked.Fig. 8 a represents that the light beam of incident can pass through, and Fig. 8 b represents that reflected light has been prevented from.
Application Example 3
The pattern displacement device is processed a birefringece crystal, makes at angle θ of its axial plane and rib, shown in Fig. 9 a.After the natural light vertical incidence, can be divided into the mutually perpendicular line polarized light of two bundle direction of vibration, shown in Fig. 9 b, be respectively o light and e light.Degree of birefringence is larger, and two-beam can separate far, is convenient to the separation of light beam.
It should be noted that herein only with ErBa
3B
9O
18, YBa
3B
9O
18, NdBa
3B
9O
18, TbBa
3B
9O
18Crystal is that example is to ReBa provided by the present invention
3B
9O
18(Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu) borate-based birefringece crystal is illustrated, but can it is evident that those skilled in the art, because the B in specific refractory power compromise characteristic and the crystal
3O
6Anionic group is relevant, and is very little with its rare earth ion relation, the ReBa that therefore can summarize this isomorphism
3B
9O
18Other crystal during (Re=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu) is borate-based also should be the uniaxial negative crystal with larger degree of birefringence.Equally, on the technical solution of the present invention basis, also can carry out variations and modifications to technical scheme of the present invention, but not break away from the scope that the present invention's claims required for protection are summarized.
Claims (3)
1. ReBa
3B
9O
18The purposes of birefringece crystal is characterized in that, described birefringece crystal is for the manufacture of light communication element, and its chemical formula is REBa
3B
9O
18, wherein RE=Y, Pr, Nd, Sm, Eu, Gd, Tb, Er, Dy, Ho, Tm, Yb and/or Lu, described crystal is transparent, is uniaxial negative crystal ne<no, and this crystal is 0.08-0.15 in the degree of birefringence ne-no of visible light wave range numerical values recited.
2. the purposes of birefringece crystal as claimed in claim 1 is characterized in that, described crystal is used for optoisolator, circulator, pattern displacement device, optical polariser or optical modulator.
3. the purposes of birefringece crystal as claimed in claim 1 is characterized in that, described crystal is used for making ahrens prism, phase delay device or electro-optical modulation device.
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CN102240848B (en) * | 2011-06-15 | 2013-10-23 | 中科中涵激光设备(福建)股份有限公司 | Method for adjusting laser beam to generate dynamic transverse displacement |
CN102586878B (en) * | 2012-03-20 | 2015-09-09 | 中国科学院新疆理化技术研究所 | Compound of barium bismuth boron oxygen and compound of barium bismuth boron oxygen optical crystal and its production and use |
CN104695016B (en) * | 2013-12-05 | 2017-04-05 | 中国科学院新疆理化技术研究所 | Boronic acid compound barium and barium borate optical crystal and preparation method and purposes |
CN106811796B (en) * | 2015-11-28 | 2019-04-16 | 中国科学院新疆理化技术研究所 | The preparation method and purposes of six lithium birefringece crystal of tetraboric acid |
CN106917139B (en) * | 2015-12-24 | 2019-10-15 | 中国科学院新疆理化技术研究所 | The preparation method and purposes of lithium metaborate crystal |
CN108070902B (en) * | 2016-11-15 | 2019-11-22 | 中国科学院新疆理化技术研究所 | Compound sodium fluoborate and sodium fluoborate birefringece crystal and preparation method and purposes |
CN106521628B (en) * | 2016-12-01 | 2021-05-25 | 新疆大学 | Lead fluorovanadate birefringent crystal and preparation method and application thereof |
CN109116635A (en) * | 2018-10-11 | 2019-01-01 | 北京航空航天大学 | A kind of liquid crystal polarization gratings preparation method |
CN113433710A (en) * | 2020-03-23 | 2021-09-24 | 广州印芯半导体技术有限公司 | Polarization beam splitting system |
CN114966906A (en) * | 2021-02-23 | 2022-08-30 | 中国科学院理化技术研究所 | Optical device for achieving interference and/or diffraction |
JPWO2024024209A1 (en) * | 2022-07-28 | 2024-02-01 |
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Non-Patent Citations (2)
Title |
---|
Ming He et al.YBa3B9O18: A Promising Scintillation Crystal.《Crystal Growth & Design》.2007,第7卷(第2期),第199页右栏第2-3段,200页左栏第3段,第201页左栏第2段、图1. * |
庄欣欣等.双折射晶体—重要的光功能材料.《结构化学》.2001,第20卷(第4期),第291页左栏第1-16行. * |
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