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

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${)}^{\mathrm{-}1/\mathrm{\mu }}$ with μ(≤1) a universal exponent. Relevance to experiments on bulk high-${\mathrm{T}}_{\mathrm{c}}$ oxides is mentioned.