Studies on Lattice Vibrations of Dielectric and Magnetic Crystals by Hyper-Raman Scattering.

对超拉曼光谱的测量进行了实验性安排，如后续，1.06<micro>米线来自声学光学Q开关Nd：YAG激光器（NEC）被用于兴奋。重复率设定在2千赫（脉冲宽度150纳秒）和6千赫（200纳秒）之间。3千瓦和50千瓦之间的峰值功率是受雇的。laser beam was focussed into the sample by a f = 5.cm lens。90 °几何中的散射光被一个多色度器（JASCO TRS-501）分散，并被一个控制器检测到一个增强的光电二极管阵列探测器（Tracor Northern）。在这个多通道检测系统的频率范围内，大约230 &lt;cm^（-1）&gt;的频率范围大致相同。在280 &lt;cm^（-1）&gt;的SrTi crystal的超拉曼光谱<O_3>内。三个波段分别在88、175和266 &lt;cm^（-1）&gt;与<nu_1>（TO， &lt;f_（1u）&gt; ）、<nu_1>（LO， &lt;f_（1u）&gt; ） +<nu_2>（TO， &lt;f_（1u）&gt; ）和<nu_4>（ &lt;f_（2u）&gt; ）对应。这些波段用于我们光谱仪的调整和波形校准。在CsCa<C1_3>中，以下五个超拉曼波段有： 76 &lt;cm^（-1）&gt; （<nu_1>LO）， 114 &lt;cm^（-1）&gt; （<nu_2>TO）， 142 &lt;cm^（-1）&gt; （<nu_2>LO）， 267 &lt;cm^（-1）&gt; （<nu_3>TO）和312 &lt;cm^（-1）&gt; （<nu_3>LO）。这些数据与从远红外反射光谱和克拉默-克罗宁分析中获得的数据进行了比较。超拉曼数据可能比远红外数据更可靠，因为（1）反射率测量取决于晶体表面条件，（2）低反射率区域的数据影响了焦函数的准确性以及TO和LO频率，从Kramers-Kronig关系计算了相关性数据的超拉曼特别。

The experimental arrangement set up for the measurement of the.hyper-Raman spectrum is as follows.The 1.06 <micro> m line from an acousto-optically Q-switched Nd:YAG laser (NEC) was used for the excitation. The repetition rate was set to between 2 KHz (pulse width 150 ns) and 6 KHz (200 ns). A peak power between 3 and 50 KW was employed. The laser beam was focussed into the sample by a f = 5.cm lens. The scattered light in the 90゜ geometry was dispersed by a polychromator (JASCO TRS-501) and detected by the intensified photodiode array detector (Tracor Northern) with a controller. In this multichannel detection system the frequency region of approximately 230 <cm^(-1)> is measured simultaneously.In the hyper-Raman spectrum below 280 <cm^(-1)> of SrTi <O_3> crystal. three bands at 88, 175 and 266 <cm^(-1)> are observed, which correspond to the <nu_1> (TO, <f_(1u)> ), <nu_1> (LO, <f_(1u)> ) + <nu_2> (TO, <f_(1u)> ) and <nu_4> ( <f_(2u)> ) respectively. These bands were used for the adjustment and wavenumber calibration of our spectrometer.In CsCa <C1_3> , the following five hyper-Raman bands were observed: 76 <cm^(-1)> ( <nu_1> LO), 114 <cm^(-1)> ( <nu_2> TO), 142 <cm^(-1)> ( <nu_2> LO), 267 <cm^(-1)> ( <nu_3> TO) and 312 <cm^(-1)> ( <nu_3> LO). These are compared with the data obtained from the far-infrared reflection spectrum and a Kramers-Kroning analysis. The hyper-Raman data might be more reliable than the far-infrared data, because (1) the reflectivity measurements depend on the condition of the crystal surface and (2) the data in the low-reflectivity region influence the accuracy of the dielectric function and the TO and LO frequencies calculated from relectivity data by Kramers-Kronig relation.The hyper-Raman spectra of several alkali halides and perovskite chlorides were measured.