Vortex-glass superconductivity: A possible new phase in bulk high-Tc oxides

The possibility of a new thermodynamic phase in the mixed state of bulk, disordered, type-II superconductors is suggested: a vortex-glass superconductor. This phase lacks conventional off-diagonal long-ranged order, yet is argued to be a true superconductor with vanishing dc resistance. In this phase metastable currents are predicted to decay as (lnt)-1 with a universal exponent. Relevance to experiments on bulk high-Tc oxides is mentioned. © 1989 The American Physical Society.