Optical Conductivity Spectral Anomalies in the Off-Center Rattling Systemβ−Ba8Ga16Sn30
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چکیده
منابع مشابه
Optical conductivity spectral anomalies in the off-center rattling system β-Ba8Ga16Sn30.
We present optical conductivity studies of the type-I clathrate Ba8Ga16Sn30, using a terahertz time-domain spectrometer (0.3-3.0 THz). The lowest-lying spectral peak at 0.72 THz due to the Ba(2) ion's off-center vibration in the oversized cage shows a drastic and anomalous temperature dependence. Below about 100 K, the single broad peak splits into two subpeaks, and with further lowering of the...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2011
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.106.015501