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退压式La3Ga5SiO14晶体电光调Q Nd:YAG激光器激光性能研究 总被引:1,自引:0,他引:1
通过对硅酸镓镧(LGS)晶体旋光性与电光效应的交互作用的理论研究,推导出晶体旋光性和电光效应共同作用下的光强表示式I=1-4B2(Asin 2ω-Ccos 2ω)2.利用此表示式设计计算了旋光晶体LGS尺寸为8 mm×8 mm× 25 mm电光Q开关在1064 nm波长使用时的开关电压和偏振角分别为4995 V和27.3°.将理论研究得到的结论应用于LGS晶体电光调Q的Nd:YAG晶体激光器的实验研究中,实验结果与理论计算结果基本一致.得到输出能量为361 mJ,脉冲宽度为7.8 ns的脉冲激光输出. 相似文献
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旋光晶体在偏光干涉实验中电光效应的研究 总被引:5,自引:3,他引:2
研究了旋光晶体在偏光干涉实验中的电光效应,给出了旋光晶体在偏光干涉实验中出射光强与晶体旋光性之间关系的表达式I—Ao^2cos^2[β-(π/λ)(n1-nr)l],以及与旋光晶体电光效应之间关系的表达式I—Ao^2cos^2[β-(π/λ)(n1-nr)l (π/λ)(n2-n1)l]。根据这些表达式给出的关系,将典型的旋光晶体La3Ga5SiO14制作成了电光Q开关,像那些用无旋光性晶体制作的Q开关一样工作良好。在中等功率输出的激光器中,La3Ga5SiO14晶体电光Q开关有可能取代氘化磷酸二氢钾(DKDP)晶体电光Q开关。 相似文献
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通过对硅酸镓镧(LGS)晶体旋光性与电光效应的交互作用的理论研究,推导出晶体旋光性和电光效应共同作用下的光强表示式I=1-4B2(Asin 2ω-Ccos 2ω)2。利用此表示式设计计算了旋光晶体LGS尺寸为8 mm×8 mm×25 mm电光Q开关在1064 nm波长使用时的开关电压和偏振角分别为4995 V和27.3°。将理论研究得到的结论应用于LGS晶体电光调Q的Nd∶YAG晶体激光器的实验研究中,实验结果与理论计算结果基本一致。得到输出能量为361 mJ,脉冲宽度为7.8 ns的脉冲激光输出。 相似文献
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本文提出了一种关于稳恒电场下由二阶电光效应感生等效透镜的理论,并分析了电场的空间特征、材料的内禀对称性及其几何形状等因素可能产生的影响.初步的估算表明,对子m3m类晶体,在10~4~10~5V的直流电压下,可观察到明显的聚焦效应. 相似文献
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双横向电光克尔效应 总被引:1,自引:0,他引:1
理论分析了克尔(Kerr)介质在两个横向电场作用下的电光调制特性.并由此确定了具有双横向电光克尔效应的光学材料种类.采用折射率椭球方法分析可知,各向同性克尔介质和一些晶体在横向外加电场作用下,其电光相位延迟与外加电场幅值的平方成正比,与电场方向无关;而其电光双折射主轴方位角与外加电场的方向角成正比,与电场幅值无关,称这种电光调制特性为双横向电光克尔效应.理论分析结果表明,排除兼有泡克耳斯(Pockels)效应和电致旋光效应的材料,立方晶系432,m3m点群和六角晶系6/mmm点群的晶体以及所有各向同性光学介质具有双横向电光克尔效应.目前已有克尔常数较大的陶瓷玻璃材料研制成功,将有力地促进双横向电光效应在光学各领域中的广泛应用. 相似文献
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利用折射率椭球分析法,分析了某些具有多重光学效应的光学晶体在两个外场同时作用下的一些特有调制规律.结果表明,当晶体的折射率椭球方程的三个交叉项中只有一项x1x2不为零时,可以得到其外场诱导新主轴折射率及其主轴取向的简单计算式.据此可以揭示出某些晶体在两个外加电场同时作用下将具有双横向电光Pockels效应,例如ˉ6点群的电光晶体.但一般晶体在双横向应力作用下不具有与双横向电光效应类似的调制特性,其弹光双折射大小与其应力差成正比,其双折射主轴方向一般为固定值.在相互垂直的外加应力和电场同时作用下,某些晶体(例如ˉ43m点群晶体)的双折射大小与外加应力和外加电场的加权几何平均值成正比,且新折射率主轴旋转角由外加应力和外加电场的比值来确定.晶体的上述双参量调制特性对设计新型光学调制器或传感器具有重要指导意义. 相似文献
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硅酸镓镧(La3Ga5SiO14,langasite,简称LGS)是一种多功能晶体。LGS和石英同属32点群,具有良好的压电和电光性质,本文在综述LGS晶体基本性质的基础上,总结了我们对这种晶体生长和性质的研究工作,测量了LGS晶体电光性质,采取措施消除旋光性影响,首次用其设计制作了电光Q开关,结果表明其效果与DKDP晶体电光Q开关相当;进而开发了高功率高重复频率Q开关,双端面泵浦模式,激光重复频率为50 KHz时,最高输出可以达到12.5瓦,脉宽为46 ns。通过改进晶体生长条件,可获得直径约50 mm,长度为100 mm,重约1000 g的光学级LGS晶体,基本满足晶体电光Q开关应用的要求。 相似文献
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Peter Herzig 《Journal of Physics and Chemistry of Solids》1982,43(5):449-454
This paper generalises the minimisation procedure for the calculation of lattice energies of cubic crystals to the cases of tetragonal, hexagonal, and trigonal crystals. If the repulsion energy is described within the simple Born-Mayer scheme minimisation of the lattice energy with respect to the lattice parameters a and c yields the repulsion parameters. The linear compressibilities obtained either by direct measurement or from the elastic constants of the crystal allow the repulsion exponent ? to be calculated. The application of this method to the tetragonal MgF2 crystal is demonstrated. 相似文献
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Yannick Petit Simon Joly Patricia Segonds Benoît Boulanger 《Laser \u0026amp; Photonics Reviews》2013,7(6):920-937
This article is mainly devoted to the modeling and measurement of the absorption and fluorescence angular distributions in polarized light of monoclinic crystals. Up to now theoretical crystal optics were mostly devoted to crystals having a high crystallographic symmetry. In these crystals belonging to the cubic, hexagonal, tetragonal, trigonal or orthorhombic lattice classes, the tensor properties related to the real part of the dielectric permittivity and to its imaginary part can be described in the same frame which orientation does not vary as a function of wavelength. The situation is much more complicated in the case of monoclinic crystals because it is necessary to define a specific frame for each property and each wavelength that are considered. The main features of monoclinic crystal optics are described in detail, followed by a review of monoclinic materials and the consequence of these features on their related optical properties. 相似文献
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Nowak B 《Solid state nuclear magnetic resonance》2002,21(1-2):53-60
General analytical formulae describing the various contributions to the total spin-lattice relaxation rate in metallic materials (single crystals or powders) are presented. The formulae are obtained in the tight-binding approximation and can be easily used for any point-group symmetry. The cubic (O(h)), hexagonal (D(3h)), and tetragonal (D(2d)) symmetries are considered in detail. 相似文献
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电光晶体在MSLM中的应用 总被引:2,自引:1,他引:1
本文利用MSLM电光调制理论对几种实用电光晶体的综合电光性能进行了理论分析和比较。讨论了材料固有的铁电相变及自然双折射等特性与器件制作工艺的兼容性问题。结果指出LiNbO3、LiTaO3、BSO是目前可以利用的三种各具特点的电光晶体。 相似文献
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Anisotropic crystals are shown to have three different mechanisms of the formation of breathers depending on the direction of the extraordinary wave propagation and on the symmetry of the medium. All uniaxial crystals with quadratic susceptibilities can be divided into three different groups, according to the crystal classes (CC). Each group is characterized by a universal structure of the breather zones (SBZ). The SBZ of the media with cubic susceptibilities does not depend neither on the crystal systems nor on the CC and coincides with the SBZ of the crystals with quadratic susceptibilities and the CC 3, 3m, 4, 4mm, 6, 6mm. 相似文献
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The phenomenological theory of the flexomagnetoelectric coupling in crystals of the cubic, tetragonal and orthorhombic crystal systems has been suggested. Secondary role of the crystal structure chirality was shown. Oppositely, significant role of the crystallographic point group type (symmetric, alternating, dihedral or cyclic) in the flexomagnetoelectric coupling has been derived. It was shown, that conceptually new features of the flexomagnetoelectric effects are expected in the crystals of the cyclic groups (crystal classes 4/m, 4? and 4). Proposed verification of the theory is investigation of the domain wall bend details (changes of the effect symmetry). Special case of such verification near the compensation point is suggested. First-principles mechanisms of the flexomagnetoelectric interaction were discussed. 相似文献
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R. Yu. Abdulsabirov M. L. Falin I. I. Fazlizhanov B. N. Kazakov S. L. Korableva I. R. Ibragimov G. M. Safiullin Zh. S. Yakovleva 《Applied magnetic resonance》1993,5(3-4):377-385
KMgF3 and KZnF3 crystals doped with Nd3+ ions were studied using EPR and optical spectroscopy methods. Several types of paramagnetic centers of Nd3+: KMgF3 — two of tetragonal and one of rhombic symmetry; KZnF3 — one of tetragonal and one of trigonal symmetry were found. Parameters of the corresponding spin Hamiltonians were determined. Using optical spectroscopy paramagnetic centers Nd2+ and Nd4+ in KMgF3 were found. 相似文献
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J. Málek 《Czechoslovak Journal of Physics》1966,16(11):884-891
A theoretical analysis is made of the influence of the crystal field with cubic, hexagonal, tetragonal and trigonal symmetries on the lifting of the degeneracy of the free Nd3+ ion energy levels and at the same time the selection rules are determined for the dipole and quadrupole transitions between the split levels for the above symmetries. 相似文献
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Vinokurov VM Gaite JM Bulka GR Khasanova NM Nizamutdinov NM Galeev AA Rudowicz C 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2002,155(1):57-63
Electron paramagnetic resonance study of a natural single crystal of natrolite was carried out at the frequency nu=36.772 GHz at room temperature. The angular dependence of the four symmetry-related spectra of Fe(3+) in the three crystallographic planes was fitted to a spin Hamiltonian (S=5/2) of symmetry C(i). The rank 4 crystal field tensors at tetrahedral sites were calculated using the point-charge model to determine the principal axes orientations of their cubic and trigonal components. The analysis of zero-field splitting tensors and comparison with crystal field ones suggests that Fe(3+) substitutes for Al(3+) with no significant distortion of the coordination tetrahedron in natrolite. Comparison of data for several natural and synthetic crystals reveals that the 4-rank zero-field splitting tensor invariants for Fe(3+) at the tetrahedral oxygen-coordinated sites are distinguishably smaller than those for Fe(3+) at octahedral sites. Such comparative analysis may help to determine the substitutional sites in other crystals. 相似文献