Pair-breaking critical current density of magnesium diboride
نویسندگان
چکیده
We report the investigation of the pair-breaking current density jd in magnesium diboride. At low current densities j, the transition temperature Tc shifts in the classic DTc( j)/Tc(0)}2@ j / jd(0)# 2/3 manner, with a projected jd(0)'2310 7 A/cm. Current-voltage curves at fixed temperatures yield a similar value for jd(0), with an overall jd(T) dependence consistent with Ginzburg-Landau theory. To our knowledge this is the first complete investigation of jd(T) down to T'0 in any superconductor.
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