Macroscopic quantum tunneling in high-$T_c$ superconductors: the role of collective charge oscillations

M. V. Fistul

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arXiv · cond-mat/0606751

Macroscopic quantum tunneling in high-$T_c$ superconductors: the role of collective charge oscillations

M. V. Fistul

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Abstract

We present a theoretical study of an escape rate for switching from the superconducting state to a resistive one in series arrays of strongly interacting Josephson junctions. At low temperatures such a switching is determined by macroscopic quantum tunneling (MQT) of a spatially extended Josephson phase. An increase of the crossover temperature from the thermal to quantum regimes, and a giant enhancement of MQT escape rate is obtained. Such an effect is explained by excitation of collective charge oscillations forming a {\it charge instanton}. Using a model of screened Coulomb interaction we found that our analysis is in a good accord with recently published experimental results on an enhancement of the MQT in single crystals of high-$T_c$ superconductors.

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M. V. Fistul. 2006-06-29. Macroscopic quantum tunneling in high-$T_c$ superconductors: the role of collective charge oscillations. https://arxiv.org/abs/cond-mat/0606751

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