Phonon spectra of La_(0.5)Ca_(0.5)MnO_3  

作　　者：曹先胜 陈长乐 

机构地区：[1]Structures and Properties,School of Science,Northwestern Polytechnical University

出　　处：《Chinese Physics B》2009年第7期2928-2932,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant No 60171034)

摘　　要：This paper presents a microscopic theory to explain different Raman modes of La0.5Ca0.5MnO3 based on the electronic Hamiltonian of the Kondo lattice model,which adds phonon interaction to the hybridization between the conduction electrons of the system and the l-electrons.The spectral density is calculated by the Green function technique of Zubarev at zero wave vector and in the low temperature limit.It finds that there are three Raman-active modes and the spectral densities of these modes are substantially influenced by model parameters such as the position of l-level （εJT）,the effective electron-phonon coupling strength （g） and the hybridization parameter （v）.Finally,the intensity changes of those peaks are investigated.This paper presents a microscopic theory to explain different Raman modes of La0.5Ca0.5MnO3 based on the electronic Hamiltonian of the Kondo lattice model,which adds phonon interaction to the hybridization between the conduction electrons of the system and the l-electrons.The spectral density is calculated by the Green function technique of Zubarev at zero wave vector and in the low temperature limit.It finds that there are three Raman-active modes and the spectral densities of these modes are substantially influenced by model parameters such as the position of l-level （εJT）,the effective electron-phonon coupling strength （g） and the hybridization parameter （v）.Finally,the intensity changes of those peaks are investigated.

关 键 词：PEROVSKITE Raman spectra 

分 类 号：O482.1[理学—固体物理]