2011/10/12 by John H. Miller, J. H. Miller Jr., Miller, J. H. +2
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #Quantum Physics (quant-ph) #Quantum and electron transport phenomena #Strongly Correlated Electrons (cond-mat.str-el) #Superconductivity (cond-mat.supr-con) #cond-mat.str-el #cond-mat.supr-con #quant-ph
paper · pdf · doi:10.48550/arxiv.1110.2537
7 pages, 6 figures
openalex publication_date 2011/10/12 · arxiv created 2012/02/06 · arxiv updated 2012/02/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We propose a magnetic dual of the Coulomb blockade effect for quantum nucleation of flux vortex pairs in high-Tc superconducting (HTS) films and grain boundaries in zero applied field. The magnetic blockade instability occurs at θ = π, where θ is the "vacuum" or theta angle. The θ term has recently been discussed in the context of several other systems, including charge and spin density waves, topological insulators, the quantum Hall effect, and spontaneous CP violation. Our model predicts a sharp pair creation threshold current at θ = π, analogous to the Coulomb blockade voltage of a tunnel junction, and explains the observed thickness dependence of critical currents in HTS coated conductors. We use the Schrödinger equation to compute the evolving macrostate amplitudes, coupled by a generalized tunneling matrix element. The simulations yield excellent quantitative agreement with measured voltage-current characteristics of bi-crystal and other HTS grain boundary junctions. The model also predicts non-sinusoidal behavior in the voltage oscillations resulting from time-correlated vortex tunneling.