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Photoacoustic wave propagating from normal into superconductive phases in Pb single crystals

Masanobu Iwanaga
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Abstract

Photoacoustic (PA) wave has been examined in a superconductor of the first kind, Pb single crystal. The PA wave is induced by optical excitation of electronic state and propagates from normal into superconductive phases below T$_{\rm C}$. It is clearly shown by wavelet analysis that the measured PA wave includes two different components. The high-frequency component is MHz-ultrasonic and the relative low-frequency one is induced by thermal wave. The latter is observed in a similar manner irrespective of T$_{\rm C}$. On the other hand, the MHz-frequency component is obviously enhanced below T$_{\rm C}$. The behavior is reproduced by the change of attenuation of longitudinal ultrasonic wave and is consistent with BCS theory.

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Masanobu Iwanaga. 2005-06-09. Photoacoustic wave propagating from normal into superconductive phases in Pb single crystals. https://doi.org/10.1103/physrevb.72.012509

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