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arXiv · 0812.4645

Effects of disorder on lattice Ginzburg-Landau model of d-wave superconductors and superfluids

Tomonori Shimizu·Shunsuke Doi·Ikuo Ichinose·Tetsuo Matsui
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Abstract

We study the effects of quenched disorder on the two-dimensional d-wave superconductors (SC's) at zero temperature by Monte-Carlo simulations. The model is defined on the three-dimesional (3D) lattice and the SC pair field is put on each spatial link as motivated in the resonating-valence-bond theory of the high-$T_{\rm c}$ SC's. For the nonrandom case, the model exhibits a second-order phase transition to a SC state as density of charge carriers is increased. It belongs to the universality class {\it different from} that of the 3D XY model. Quenched disorders (impurities) are introduced both in the hopping amplitude and the plaquette term of pair fields. Then the second-order transition disappears at a critical concentration of quenched disorder, $p_c\simeq 15%$. Implication of the results to cold atomic systems in optical lattices is also discussed.

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Tomonori Shimizu, Shunsuke Doi, Ikuo Ichinose, Tetsuo Matsui. 2008-12-26. Effects of disorder on lattice Ginzburg-Landau model of d-wave superconductors and superfluids. https://doi.org/10.1103/physrevb.79.092508

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