Anomalous temperature dependence of the optical phonon properties of Ba1−xKxBiO3 single crystals
| Autor: | Javed Ahmad, Hiromoto Uwe |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Kramers–Kronig relations
Materials science Condensed matter physics Phonon Exciton Energy Engineering and Power Technology Condensed Matter Physics Optical conductivity Spectral line Electronic Optical and Magnetic Materials Amplitude Far infrared Condensed Matter::Superconductivity Condensed Matter::Strongly Correlated Electrons Electrical and Electronic Engineering Charge density wave |
| Zdroj: | Physica C: Superconductivity. :288-292 |
| ISSN: | 0921-4534 |
| DOI: | 10.1016/j.physc.2004.01.053 |
| Popis: | 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, σ1(ω,T). The integrated σ1(ω,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. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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