New effects in absorption of ultrasound in intermediate state of high pure type I superconductor

TL;DR

This study investigates ultrasound absorption in high purity Gallium superconductors, revealing new oscillatory effects and maxima in absorption related to the intermediate state and magnetic field variations.

Contribution

It reports the discovery of new ultrasound absorption effects and oscillations in high purity Gallium, along with proposed theoretical explanations for these phenomena.

Findings

Observed large oscillations in ultrasound absorption below critical magnetic field.

Identified maximum monotonic ultrasound absorption in the intermediate state.

Proposed theoretical mechanisms for the observed oscillations.

Abstract

The research on the longitudinal ultrasound absorption in an intermediate state of the high pure Gallium single crystal at the frequency of 50-190MHz at the temperatures of 0,37-0,75 K, using the impulse method, is conducted. The new effects in the absorption of ultrasound in an intermediate state of the high pure type I superconductor are discovered. The big oscillations in the dependence of the ultrasound absorption on the magnetic field in an intermediate state of the high pure Gallium single crystal are experimentally observed at the magnitudes of magnetic field below the critical magnetic field. The maximum of the monotonic absorption of longitudinal ultrasound in an intermediate state of the high pure type I superconductor is also obtained. The possible original theoretical mechanisms to explain the nature of big oscillations in the dependence of the ultrasound absorption on the magnetic field in an intermediate state of the high pure type I superconductor are proposed.