Fj. Owens et al., MAGNETOMICROWAVE ABSORPTION STUDY OF FLUX DEPINNING IN HG0.7PB0.3BA2CA2CU3O8 SUPERCONDUCTOR, Physica. C, Superconductivity, 233(1-2), 1994, pp. 30-34
The microwave absorption in the superconducting state of single-phase
Hg0.7Pb0.3Ba2Ca2Cu3O8+x having a T-c of 133 K is shown to depend linea
rly on the square root of the DC magnetic field strength with a change
of slope occurring at a DC magnetic field B which corresponds to an
onset of an irreversibility in the field dependence of the microwave a
bsorption. A measurement of the temperature dependence of B enables a
determination of an H-T irreversibility line at 9.2 GHz. A comparison
of the magnetic-field-induced dissipation with that the Y-Ba-Cu-O ind
icates that the Hg-Pb-Ba-Ca-Cu-O material has a larger pinning barrier
to flux detrapping at 77 K.