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arXiv · 1210.0991

Breakdown of the cross-Kerr scheme for Photon Counting

Bixuan Fan·Anton F. Kockum·Joshua Combes·Göran Johansson·Io-chun Hoi·Christopher Wilson·Per Delsing·G. J. Milburn·Thomas M. Stace
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Abstract

We show, in the context of single photon detection, that an atomic three-level model for a transmon in a transmission line does not support the predictions of the nonlinear polarisability model known as the cross-Kerr effect. We show that the induced displacement of a probe in the presence or absence of a single photon in the signal field, cannot be resolved above the quantum noise in the probe. This strongly suggests that cross-Kerr media are not suitable for photon counting or related single photon applications. Our results are presented in the context of a transmon in a one dimensional microwave waveguide, but the conclusions also apply to optical systems.

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Bixuan Fan, Anton F. Kockum, Joshua Combes, Göran Johansson, Io-chun Hoi, Christopher Wilson, Per Delsing, G. J. Milburn, Thomas M. Stace. 2012-10-03. Breakdown of the cross-Kerr scheme for Photon Counting. https://doi.org/10.1103/physrevlett.110.053601

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