2014/11/30 by Andreas Andersson, Andréas Andersson, Jack Lidmar
Physics and Astronomy · #Amplitude #Condensed matter physics #Instanton #Insulator (electricity) #Josephson effect #Phase (matter) #Physics #Physics of Superconductivity and Magnetism #Quantum #Quantum and electron transport phenomena #Quantum mechanics #Quantum tunnelling #Scaling #Superconductivity #Theoretical and Computational Physics #cond-mat.mes-hall #cond-mat.quant-gas #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.91.134504
published as Phys. Rev. B 91, 134504 (2015) · 12 pages, 11 figures
openalex publication_date 2015/04/10 · arxiv created 2015/04/16 · arxiv updated 2015/04/17 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We study quantum phase slips (QPS) in ultrathin superconducting wires. Starting from an effective one-dimensional microscopic model, which includes electromagnetic fluctuations, we map the problem to a (1+1)-dimensional gas of interacting instantons. We introduce a method to calculate the tunneling amplitude of quantum phase slips directly from Monte Carlo simulations. This allows us to go beyond the dilute instanton gas approximation and study the problem without any limitations of the density of QPS. We find that the tunneling amplitude shows a characteristic scaling behavior near the superconductor-insulator transition. We also calculate the voltage-charge relation of the insulating state, which is the dual of the Josephson current-phase relation in ordinary superconducting weak links. This evolves from a sinusoidal form in the regime of dilute QPS to more exotic shapes for higher QPS densities, where interactions are important.