A new IR excitation in semiconducting Ba1-xKxBiO3 single crystals

被引：7

作者：

Ahmad, J ^{[1
]}

Nishio, T ^{[1
]}

Uwe, H ^{[1
]}

机构：

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

来源：

PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS | 2003年 / 388卷

关键词：

Ba1-xKxBiO3; optical reffectivity; CDW; spectral weight;

D O I：

10.1016/S0921-4534(02)02575-3

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We report optical reflectivity measurements on Ba1-xKBiO3 (x = 0, 0. 15) single crystals in the frequency range 70-30 000 cm(-1) and at different temperatures in an attempt to understand the transport mechanism in the semiconducting state before it undergoes semiconductor-metal transition. For x = 0. 15, at 400 K, we find a hump in reflectivity at approximate to 1280 cm(-1). N-eff of total IR transition shifts towards low frequency as temperature increases above 300 K. We suggest the presence of new and thermally excited states in the Peierls band gap and the possible new IR excitations. (C) 2003 Elsevier Science B.V. All rights reserved.

引用

页码：455 / 456

页数：2