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arXiv:cond-mat/9504031 · Physical Review Letters

Magnetization Relaxation via Quantum and Classical Vortex Motion in a Bose Glass Superconductor

Leo Radzihovsky

Published Jun 12, 1995• 23 citations
arXivHTMLPDF

Abstract

I show that in a Bose glass superconductor with high ${j}_{c}$ and at low $T$ the magnetization relaxation ( $S$), dominated by quantum tunneling, is $\ensuremath{\propto}\sqrt{{j}_{c}}$, which crosses over to the conventional classical rate $\ensuremath{\propto}T/{j}_{c}$ at higher $T$ and lower ${j}_{c}$, with the crossover ${T}^{*}\ensuremath{\sim}{j}_{c}^{3/2}$. I argue that due to interactions between flux lines there exist three relaxation regimes, depending on whether $B<{B}_{\ensuremath{\varphi}}$, $B\ensuremath{\approx}{B}_{\ensuremath{\varphi}}$, $B>{B}_{\ensuremath{\varphi}}$, corresponding to strongly pinned Bose glass with large ${j}_{c2}$, Mott insulator with vanishing $S$, and weakly pinned Bose glass characterized by small ${j}_{c1}$. I discuss the effects of interactions on ${j}_{c}$ and focus attention on a recent experiment which is consistently described by the theory.

DOI
10.1103/physrevlett.74.4919

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