Magnetic hysteresis in the microwave surface resistance of Nb samples in the critical state

Abstract

We discuss the hysteretic behavior of the field-induced variations of the microwave surface resistance in superconductors in the critical state. Measurements have been performed in a bulk sample of Nb and a powdered one at different values of the temperature. We discuss a model, based on the Coffey and Clem theory, in which we take into account the flux distribution inside the sample, due to the critical state. The experimental results are justified quantitatively in the framework of our model. We show that by fitting the experimental data it is possible to determine the value of the critical current density and its field dependence.

8 pages, 10 embedded figures, submitted to Eur. Phys. J. B

References in corpus (3)

• Critical-state effects on microwave losses in type-II superconductors
• Microwave Properties of Ba(0.6)K(0.4)BiO(3) Crystals
• Microwave Surface Resistance and Upper-Critical-Field Anisotropy of MgB2 Superconductor

Cited by in corpus (4)

• Depinning frequency in a heavily neutron-irradiated MgB2 sample
• Microwave surface resistance of pristine and neutron-irradiated MgB2 samples in magnetic field
• Field-induced suppression of the pi-band superconductivity and magnetic hysteresis in the microwave surface resistance of MgB_2 at temperatures near T_c
• Anomalous magnetic hysteresis in the microwave surface resistance of MgB2 superconductor