Reduction in energy dissipation rate with increased effective applied field

TL;DR

This paper investigates how the energy dissipation rate in type-II superconductors varies with different magnetic field waveforms and hysteresis types, supported by experimental data aligning with theoretical predictions.

Contribution

It provides experimental validation of energy dissipation models for rate-independent and rate-dependent hysteresis in superconductors under varying magnetic fields.

Findings

Energy dissipation depends on waveform and hysteresis type.

Experimental data confirms critical state theory predictions.

Different behaviors observed in normal and superconducting states.

Abstract

Dynamics of the response of type-II superconductors to a time-varying magnetic field can exhibit a rate-independent or rate-dependent hysteresis. An energy dissipation rate in a superconductor placed in a time-varying magnetic field depends on its wave form and type of hysteresis, which depends on temperature. The same wave form may reduce the energy dissipation rate in the case of true hysteresis, while it may increase the energy dissipation rate in the case of dynamic hysteresis compared with an energy dissipation rate in a pure sinusoidal field. We present experimental data which confirm the energy dissipation rate calculated using the critical state theory for the case of rate-independent hysteresis and limiting behavior in a normal state for the case of rate-dependent hysteresis.