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arXiv · cond-mat/9811149

A new broken U(1)-symmetry in extreme type-II superconductors

A. K. Nguyen·A. Sudbø
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Abstract

A phase transition within the molten phase of the Abrikosov vortex system without disorder in extreme type-II superconductors is found via large-scale Monte-Carlo simulations. It involves breaking a U(1)-symmetry, and has a zero-field counterpart, unlike vortex lattice melting. Its hallmark is the loss of number-conservation of connected vortex paths threading the entire system {\it in any direction}, driving the vortex line tension to zero. This tension plays the role of a generalized ``stiffness'' of the vortex liquid, and serves as a probe of the loss of order at the transition, where a weak specific heat anomaly is found.

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A. K. Nguyen, A. Sudbø. 1999-05-31. A new broken U(1)-symmetry in extreme type-II superconductors. https://doi.org/10.1209/epl%2Fi1999-00332-7

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