Transverse Ultrasonic Attenuation in Gapless Superconductors

Abstract

We present here the calculation of the ultrasonic attenuation coefficient of the transverse waves in the gapless superconductors, such as type-II superconductors in a high magnetic field. Particular attention is paid to the electromagnetic absorption term, which is important in the present case, and the result obtained is a simple generalization of that due to Kadanoff and Falko. We discuss ultrasonic attenuation in type-II superconductors, as well as in a superconducting surface sheath in a field above $H_{c2\mathrm{}}$.