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Monte-Carlo calculation of longitudinal and transverse resistivities in a model Type-II superconductor

T. J. Hagenaars·E. H. Brandt
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Abstract

We study the effect of a transport current on the vortex-line lattice in isotropic type-II superconductors in the presence of strong thermal fluctuations by means of 'driven-diffusion' Monte Carlo simulations of a discretized London theory with finite magnetic penetration depth. We calculate the current-voltage (I-V) characteristics for various temperatures, for transverse as well as longitudinal currents I. From these characteristics, we estimate the linear resistivities R_xx=R_yy and R_zz and compare these with equilibrium results for the vortex-lattice structure factor and the helicity moduli. From this comparison a consistent picture arises, in which the melting of the flux-line lattice occurs in two stages for the system size considered. In the first stage of the melting, at a temperature T_m, the structure factor drops to zero and R_xx becomes finite. For a higher temperature T_z, the second stage takes place, in which the longitudinal superconducting coherence is lost, and R_zz becomes finite as well. We compare our results with related recent numerical work and experiments on cuprate superconductors.

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T. J. Hagenaars, E. H. Brandt. 1997-07-21. Monte-Carlo calculation of longitudinal and transverse resistivities in a model Type-II superconductor. https://doi.org/10.1103/physrevb.56.r11435

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