Observation of Transition from Escape Dynamics to Underdamped Phase Diffusion in a Josephson Junction

2005/01/17 by J. M. Kivioja, Jani Kivioja, Tommi Nieminen +6 · 2 citations
Computer Science · Physics and Astronomy · #Nonlinear Dynamics and Pattern Formation #Quantum Information and Cryptography #Quantum and electron transport phenomena #cond-mat.mes-hall #cond-mat.supr-con

paper · pdf · doi:10.1103/physrevlett.94.247002

4 pages, 3 figures

arxiv created 2005/01/17 · openalex publication_date 2005/06/22 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04

Abstract

We have investigated the dynamics of underdamped Josephson junctions with a relatively small Josephson coupling E_J. In addition to the usual crossover between macroscopic quantum tunneling and thermally activated (TA) behavior we observe, for the first time, the transition from TA behavior to underdamped phase diffusion. Above the crossover temperature, the threshold for switching into the finite-voltage state becomes extremely sharp. We propose a (T, E_J) phase diagram with various regimes and show that for a proper description of it, dissipation and level quantization in a metastable well are crucial.

Citations

• Multiphoton Transitions in a Macroscopic Quantum Two-State System

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