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Updated: Jun 8, 2026

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Asymmetric long josephson junction acting as a ratchet for a quantum field
A O Sboychakov1, Sergey Savel'ev, A L Rakhmanov
1Advanced Science Institute, RIKEN, Wako-shi, Saitama, 351-0198, Japan.
Abstract:
We study the escape rate of flux quanta in a long Josephson junction having an asymmetric spatial inhomogeneous critical current density. Such a junction can behave as a ratchet when driven by an ac current in the presence of a magnetic field. This rectification gives rise to a dc voltage V(dc) across the junction. The usual approach of particlelike tunneling cannot describe this rectification, and a quantum field theory description is required. We also show that, under specific conditions, the rectification direction, and consequently V(dc), can change its sign when varying the temperature T near the crossover temperature T* between the quantum and classical regimes.
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