Vortex flow and transverse flux screening at the Bose glass transition

Abstract

We study the vortex phase diagram in untwinned YBCO crystals with colunmar defects. These randomly distributed defects are expected to induce a "Bose glass'' phase of localized vortices exhibiting a vanishing resistance and Meissner effect for magnetic fields H⊥ to transverse to the columns. We directly observe the transverse Meissner effect using a Hall probe array. As predicted, the Meissner state breaks down at temperatures T_s that decrease linearly as H⊥ to increases. However, T_s lies far below the conventional melting temperature T_m determined by a vanishing resistivity, suggesting a regime where vortices are effectively localized even when rotated off the columnar defects.

Files

Additional details