EPR Effect in Magnetic Dependent Dissipation in High Temperature Superconductors
نویسنده
چکیده
Electron paramagnetic resonance in ac dissipation was observed due to the Cooper pairs breaking up to their quasiparticle state. This phenomenon is the result of a flux motion on a pinning centers in high temperature superconducting materials. The detection of ac dissipation was performed in a low ac field (15 and 22 MHz) as well as in microwave range. Vortex motion hysteresis loop with magnetic field modulation of 15 Hz was recorded. Besides V-shaped dependence of ac power dissipation P (B), a direct electron paramagnetic resonance signal related to Cooper pairs → quasiparticle fluctuation was observed.
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