RANDOM-PHASE-APPROXIMATION APPROACH TO PHONON-SPECTRA IN DOPED AND UNDOPED HALOGEN-BRIDGED TRANSITION-METAL COMPOUNDS

被引:29
作者
BATISTIC, I [1 ]
BISHOP, AR [1 ]
机构
[1] UNIV CALIF LOS ALAMOS SCI LAB, DIV THEORET, LOS ALAMOS, NM 87545 USA
来源
PHYSICAL REVIEW B | 1992年 / 45卷 / 10期
关键词
D O I
10.1103/PhysRevB.45.5282
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
We have developed a method based on a real-space random-phase approximation (RPA) to study the phonon spectra of doped and undoped halogen-bridged transition-metal-chain complexes. The method is very convenient in cases of spatially inhomogeneous mean-field structures. Thus, we are able to find the usual extended phonon modes as well as local modes associated with polaron, bipolaron, kink, exciton, or impurity structures in intrinsically or extrinsically doped systems. The corresponding infrared absorption spectra and Raman spectra (as a function of the excitation energy) are calculated. We demonstrate the method for a homogeneous charge-density-wave system, and for electron and hole polarons. We find that each type of defect has specific signatures in both infrared and Raman spectra, which can help to identify different types of defects experimentally.
引用
收藏
页码:5282 / 5292
页数:11
相关论文
共 32 条
[1]  
[Anonymous], 1983, QUANTUM THEORY LIGHT
[2]   LOCALIZED POLARONIC STATES IN MIXED-VALENCE LINEAR-CHAIN COMPLEXES [J].
BAERISWYL, D ;
BISHOP, AR .
JOURNAL OF PHYSICS C-SOLID STATE PHYSICS, 1988, 21 (02) :339-356
[3]   HALOGEN-BRIDGED METAL-COMPLEXES - MODEL COMPOUNDS FOR HIGH-TC SUPERCONDUCTORS [J].
BAERISWYL, D ;
BISHOP, AR .
PHYSICA SCRIPTA, 1987, T19A :239-245
[4]   SELF-CONSISTENT ELECTRON-PHONON COUPLING IN TIGHT-BINDING APPROXIMATION .2. [J].
BARISIC, S .
PHYSICAL REVIEW B, 1972, 5 (03) :941-&
[5]   RIGID-ATOM ELECTRON-PHONON COUPLING IN TIGHT-BINDING APPROXIMATION .1. [J].
BARISIC, S .
PHYSICAL REVIEW B, 1972, 5 (03) :932-&
[6]  
BISHOP AR, 1989, SYNTHETIC MET, V29, pF151, DOI 10.1016/0379-6779(89)90893-X
[7]  
Blaizot J.-P., 1986, QUANTUM THEORY FINIT
[8]  
CLARK RJH, 1983, ADV INFRARED RAMAN S, V11, P95
[9]   FAR-INFRARED OPTICAL INVESTIGATIONS ON QUASI-ONE-DIMENSIONAL HALOGEN-BRIDGED MIXED-VALENCE COMPOUNDS [J].
DEGIORGI, L ;
WACHTER, P ;
HARUKI, M ;
KURITA, S .
PHYSICAL REVIEW B, 1989, 40 (05) :3285-3293
[10]   THEORY AND PROPERTIES OF RANDOMLY DISORDERED CRYSTALS AND RELATED PHYSICAL SYSTEMS [J].
ELLIOTT, RJ ;
KRUMHANS.JA ;
LEATH, PL .
REVIEWS OF MODERN PHYSICS, 1974, 46 (03) :465-543