The magnetic-field-induced variations of the microwave Surface resistance have been investigated in a heavily neutron-irradiated MgB2 sample, in which the irradiation has Caused the merging of the two gaps into a single value. The experimental results have been analyzed in the framework of the Coffey and Clem model. By fitting the experimental data, we have determined the field dependence of the depinning frequency, omega(0), at different Values of the temperature. Although the pinning is not particularly effective, the value of omega(0) obtained at low temperatures is considerably higher than that observed in conventional low-temperature superconductors. (C) 2008 Elsevier B.V. All rights reserved.
Depinning frequency in a heavily neutron-irradiated MgB2 sample
Martinelli A
2008
Abstract
The magnetic-field-induced variations of the microwave Surface resistance have been investigated in a heavily neutron-irradiated MgB2 sample, in which the irradiation has Caused the merging of the two gaps into a single value. The experimental results have been analyzed in the framework of the Coffey and Clem model. By fitting the experimental data, we have determined the field dependence of the depinning frequency, omega(0), at different Values of the temperature. Although the pinning is not particularly effective, the value of omega(0) obtained at low temperatures is considerably higher than that observed in conventional low-temperature superconductors. (C) 2008 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
