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arXiv · 1911.02817

Superconductor-insulator transition in Josephson junction chains by quantum Monte-Carlo

D. M. Basko·F. Pfeiffer·P. Adamus·M. Holzmann·F. W. J. Hekking
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Abstract

We study the zero-temperature phase diagram of a dissipationless and disorder-free Josephson junction chain. Namely, we determine the critical Josephson energy below which the chain becomes insulating, as a function of the ratio of two capacitances: the capacitance of each Josephson junction and the capacitance between each superconducting island and the ground. We develop an imaginary-time path integral Quantum Monte-Carlo algorithm in the charge representation, which enables us to efficiently handle the electrostatic part of the chain Hamiltonian. We find that a large part of the phase diagram is determined by anharmonic corrections which are not captured by the standard Kosterlitz-Thouless renormalization group description of the transition.

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D. M. Basko, F. Pfeiffer, P. Adamus, M. Holzmann, F. W. J. Hekking. 2019-11-07. Superconductor-insulator transition in Josephson junction chains by quantum Monte-Carlo. https://doi.org/10.1103/physrevb.101.024518

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