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Conference on Lasers and Electro-Optics

Quantum information with superconducting quantum bits and cavities

Raymond W. Simmonds

Published May 1, 2008• 0 citations
Publisher

Abstract

We have implemented cavity quantum-electro dynamics, in the strong coupling regime, using superconducting phase qubits and a resonant transmission line cavity. We have observed coherent quantum interactions with cavity decay times over one microsecond.
DOI
10.1109/cleo.2008.4551954

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We present a detailed characterization of coherence in seven transmon qubits in a circuit QED architecture. We find that spontaneous emission rates are strongly influenced by far off-resonant modes of the cavity and can be understood within a semiclassical circuit model. A careful analysis of the spontaneous qubit decay into a microwave transmission-line cavity can accurately predict the qubit lifetimes over 2 orders of magnitude in time and more than an octave in frequency. Coherence times T1 and T_{2};{*} of more than a microsecond are reproducibly demonstrated.
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