J. Phys. IV France 09 (1999) Pr10-49-Pr10-51
Spin-echo observation of radio frequency induced flux lattice annealing (RIFLA) in a type-II superconductorW.G. Clark1, F. Lefloch2, M.E. Hanson1 and W.H. Wong3
1 UCLA Department of Physics and Astronomy, Box 951547, Los Angeles, CA 90095-1547, U.S.A.
2 CEA, Grenoble, France
3 Varian Associates, Palo Alto, CA, U.S.A.
We report the annealing of a strained flux line lattice (FLL) in 10 µm diameter type-II superconducting NbTi filaments by an rf magnetic field at 4.2 K in a magnetic field of 1 T. The strained FLL is prepared by slowly changing the direction of the applied magnetic field. When the rf magnetic field used to generate a 93Nb NMR spin echo anneals the FLL, there is a corresponding reduction in the amplitude of the spin echo. Starting from an annealed condition, a rotation threshold of 3 mr is needed to produce enough FLL strain to be observed in these measurements.
© EDP Sciences 1999