Published June 1996 | Version v1
Journal article

Radio-frequency magnetoabsorption in YBCO-Ag and BSCCO superconductors: the cross-over between two-level and one-level critical state models

  • 1. Department of Physics and Meteorology, Indian Institute of Technology, Kharagpur (India)

Description

We have studied the virgin curve and hysteresis of radio-frequency magnetoabsorption in YBCO-Ag(YBa2Cu3O7-δ:Ag1.2) and BSCCO (Bi2Sr2CaCu2O8+δ) samples at 77 K in a magnetic field up to a value of 2 kOe. The hysteresis of YBCO-Ag is in good agreement with the prediction of the two-level critical state model. However, in the case of BSCCO the agreement is there only when the maximum field does not exceed 67.5 Oe for a frequency of 1.5 MHz. For higher fields the results resemble those of the one-level critical state model. This is due to the fact that at fields greater than 67.5 Oe the superconducting grain boundaries become normal. The cross-over point shifts to 55 Oe when the frequency is increased to 12 MHz. A qualitative explanation of this shift is given on the basis of the disordered model. (author)

Availability note (English)

Available online at the Web site for the journal Superconductor Science and Technology (ISSN 1361-6668) http://www.iop.org/

Additional details

Identifiers

Publishing Information

Journal Title
Superconductor Science and Technology
Journal Volume
9
Journal Issue
6
Journal Page Range
p. 447-452
ISSN
0953-2048