Intrinsic Dissipation in Superconducting Junctions Probed by Qubit Spectroscopy

Research output: Contribution to journalArticleScientificpeer-review


Research units

  • RAS - P.N. Lebedev Physics Institute
  • Karlsruhe Institute of Technology
  • National Research University Higher School of Economics


The study of frequency-dependent intrinsic dissipation in a highly transparent Josephson junction by means of quantum-bit (qubit) spectroscopy is proposed. The spectral density of the effective dissipative bath may contain significant contributions from Andreev bound states coupled to fluctuations of the Josephson phase. Varying either the bias current applied to the junction or magnetic flux through a superconducting ring in the radiofrequency superconducting quantum interference device (rf-SQUID) setup, one can tune the level splitting value close to the bottom of the Josephson potential well. Monitoring the qubit energy relaxation time one can probe the spectral density of the effective dissipative bath and unambiguously identify the contribution emerging from Andreev levels.


Original languageEnglish
Article number1800256
Pages (from-to)1-7
JournalPhysica Status Solidi - Rapid Research Letters
Issue number1
Publication statusPublished - Jan 2019
MoE publication typeA1 Journal article-refereed

    Research areas

  • Andreev levels, dissipation, Josephson junctions, quantum bits, qubit spectroscopy

ID: 28349231