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Decoherence in a superconducting quantum bit circuit

G. Ithier·E. Collin·P. Joyez·P. J. Meeson·D. Vion·D. Esteve·F. Chiarello·A. Shnirman·Y. Makhlin·J. Schriefl·G. Schon
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Abstract

Decoherence in quantum bit circuits is presently a major limitation to their use for quantum computing purposes. We present experiments, inspired from NMR, that characterise decoherence in a particular superconducting quantum bit circuit, the quantronium. We introduce a general framework for the analysis of decoherence, based on the spectral densities of the noise sources coupled to the qubit. Analysis of our measurements within this framework indicates a simple model for the noise sources acting on the qubit. We discuss various methods to fight decoherence.

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G. Ithier, E. Collin, P. Joyez, P. J. Meeson, D. Vion, D. Esteve, F. Chiarello, A. Shnirman, Y. Makhlin, J. Schriefl, G. Schon. 2005-08-24. Decoherence in a superconducting quantum bit circuit. https://doi.org/10.1103/physrevb.72.134519

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