OPTICAL PHONONS AND SYMMETRY OF TYSONITE LANTHANIDE FLUORIDES

被引：39

作者：

LOWNDES, RP

PARRISH, JF

PERRY, CH

机构：

[1] Spectroscopy Laboratory and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge

[2] Department of Physics, Northeastern University, Boston

来源：

PHYSICAL REVIEW | 1969年 / 182卷 / 03期

基金：

美国国家科学基金会; 美国国家航空航天局;

关键词：

D O I：

10.1103/PhysRev.182.913

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The polarized infrared reflectance of LaF3, CeF3, PrF3, and NdF3 has been measured from 40 to 500 cm-1 at 295, 78, and 7°K. Kramers-Kronig analyses of the reflectance spectra yield evidence for eleven infraredactive phonons in the polarization (Ec) and six in the polarization (Ec). These results, together with reported magnetic-resonance measurements, are consistent with a P3c1 magnetic space group. A theory and method for directly observing the longitudinal optical phonon frequencies of strongly anisotropic crystals in transmission are reported. © 1969 The American Physical Society.

引用

页码：913 / &