Dissipative Landau-Zener transitions of a qubit: Bath-specific and universal behavior

Keiji Saitou, Martijn Wubs, Sigmund Kohler, Yosuke Kayanuma, Peter Hänggi

Research output: Contribution to journalArticle

94 Citations (Scopus)

Abstract

We study Landau-Zener transitions in a qubit coupled to a bath at zero temperature. A general formula that is applicable to models with a nondegenerate ground state is derived. We calculate exact transition probabilities for a qubit coupled to either a bosonic or a spin bath. The nature of the baths and the qubit-bath coupling is reflected in the transition probabilities. For diagonal coupling, when the bath causes energy fluctuations of the diabatic qubit states but no transitions between them, the transition probability coincides with the standard Landau-Zener probability of an isolated qubit. This result is universal as it does not depend on the specific type of bath. For pure off-diagonal coupling, by contrast, the tunneling probability is sensitive to the coupling strength. We discuss the relevance of our results for experiments on molecular nanomagnets, in circuit QED, and for the fast-pulse readout of superconducting phase qubits.

Original languageEnglish
Article number214308
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume75
Issue number21
DOIs
Publication statusPublished - 2007 Jun 29
Externally publishedYes

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baths
transition probabilities
Electron transitions
Ground state
readout
Networks (circuits)
ground state
causes
pulses
Experiments
Temperature
temperature
energy

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Dissipative Landau-Zener transitions of a qubit : Bath-specific and universal behavior. / Saitou, Keiji; Wubs, Martijn; Kohler, Sigmund; Kayanuma, Yosuke; Hänggi, Peter.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 75, No. 21, 214308, 29.06.2007.

Research output: Contribution to journalArticle

Saitou, Keiji ; Wubs, Martijn ; Kohler, Sigmund ; Kayanuma, Yosuke ; Hänggi, Peter. / Dissipative Landau-Zener transitions of a qubit : Bath-specific and universal behavior. In: Physical Review B - Condensed Matter and Materials Physics. 2007 ; Vol. 75, No. 21.
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