Numerical study of the strongly screened vortex-glass model in an external field
نویسندگان
چکیده
The vortex-glass model for a disordered high-Tc superconductor in an external magnetic field is studied in the strong screening limit. With exact ground state ~i.e., T50) calculations we show that ~1! the ground state of the vortex configuration varies drastically with infinitesimal variations of the strength of the external field; ~2! the minimum energy of global excitation loops of length scale L do not depend on the strength of the external field; however, ~3! the excitation loops themself depend sensibly on the field. From ~2! we infer the absence of a true superconducting state at any finite-temperature independent of the external field. @S0163-1829~99!08133-3#
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