Anomalous temperature dependence of the optical phonon properties of Ba1-xKxBiO3 single crystals

被引：7

作者：

Ahmad, J ^{[1
]}

Uwe, H ^{[1
]}

机构：

[1] Univ Tsukuba, Inst Mat Sci, Uwe Minami Lab, Tsukuba, Ibaraki 3058573, Japan

来源：

PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS | 2004年 / 412卷

关键词：

B1-xKxBiO3; CDW; spectral weight; optical phonon exciton interaction;

D O I：

10.1016/j.physc.2004.01.053

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Temperature dependence of optical phonon properties of Ba1-xKxBiO3 (x = 0, 0.15) single crystals is investigated by far infrared optical reflectivity measurements. The Kramers Kronig (KK) analysis of the reflectivity spectra yields real part of complex optical conductivity, sigma(1)(omega, T). The integrated sigma(1)(omega, T) is found to decrease with increasing temperature in contrast to the conventionally temperature independent behavior of phonons. The change noticed in the spectral weight of all individual phonons suggests the coupling of phonons with some high-energy excitations in addition to the suppression of charge density wave (CDW) amplitude. We propose interaction of phonons with the indirect excitons as one of the possibilities. (C) 2004 Published by Elsevier B.V.

引用

页码：288 / 292

页数：5

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