Energy relaxation of superconducting charge qubit via Andreev processes

Abstract

We study fundamental limitations on the energy relaxation rate of a superconducting charge qubit with a large-gap Cooper-pair box, ${\Delta }_b>{\Delta }_r$. At a sufficiently large mismatch between the gap energies in the box ${\Delta }_b$ and in the reservoir ${\Delta }_r$,"quasiparticle poisoning" becomes ineffective even in the presence of nonequilibrium quasiparticles in the reservoir. The qubit relaxation still may occur due to higher-order (Andreev) processes. In this paper we evaluate the qubit energy relaxation rate due to Andreev processes.

6 pages, 4 figures (accepted to Phys. Rev. B)

References in corpus (5)

• Quasiparticle decay rate of Josephson charge qubit oscillations
• Microsecond resolution of quasiparticle tunneling in the single-Cooper-pair-transistor
• Time-domain measurements of quasiparticle tunneling rates in a single-Cooper-pair transistor
• Kinetics of the superconducting charge qubit in the presence of a quasiparticle
• Parity effect in superconducting aluminum single electron transistors with spatial gap profile controlled by film thickness

Cited by in corpus (1)

• Dissipation-driven quantum phase transition in superconductor-graphene systems