Field distribution and flux-line depinning in MgB (2).
We report the first observation of the field distribution and flux-line lattice (FLL) depinning in the vortex-state (VS) of a type-II superconductor probed by conduction electron spin resonance (CESR). CESR was performed in MgB (2) (T(c) approximately 39 K) at 4.1 GHz (1455 Oe) and 9.5 GHz (3390 Oe). The field distribution, n(H), and a standard deviation of sigma approximately 14 Oe (at 28 K/4.1 GHz and at 7 K/9.5 GHz) were inferred, respectively, from the distortion and broadening of the CESR in the VS. For both frequencies, the FLL depinning temperature was determined.
IFGW-UNICAMP, 13083-970 Campinas-SP, Brazil.
R R
RR
Urbano
P G
PG
Pagliuso
C
C
Rettori
Y
Y
Kopelevich
N O
NO
Moreno
J L
JL
Sarrao