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arXiv · 1609.01683

Ultrasonic attenuation in a pseudogapped superconductor

A. V. Shtyk·M. V. Feigel'man
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Abstract

We develop a theory of ultrasound decay rate $\alpha$ in a model of a superconductor with a large pseudogap $\Delta_P$, and show that at low temperatures ($T \ll T_c$) the magnitude of the decay rate $\alpha$ is controlled by the ratio of $T/\Delta$, where $\Delta \ll \Delta_P$ is a superconducting collective gap. Thus we propose new method to measure the collective gap $\Delta$ in a situation when strong pseudogap is present.

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A. V. Shtyk, M. V. Feigel'man. 2016-09-06. Ultrasonic attenuation in a pseudogapped superconductor. https://doi.org/10.1103/physrevb.96.064523

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