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arXiv · 0812.2151

Quantum Zeno switch for single-photon coherent transport

Lan Zhou·S. Yang·Yu-xi Liu·C. P. Sun·Franco Nori
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Abstract

Using a dynamical quantum Zeno effect, we propose a general approach to control the coupling between a two-level system (TLS) and its surroundings, by modulating the energy level spacing of the TLS with a high frequency signal. We show that the TLS--surroundings interaction can be turned on or off when the ratio between the amplitude and the frequency of the modulating field is adjusted to be a zero of a Bessel function. The quantum Zeno effect of the TLS can also be observed by the vanishing of the photon reflection at these zeros. Based on these results, we propose a quantum switch to control the transport of a single photon in a 1D waveguide. Our analytical results agree well with numerical results using Floquet theory.

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Lan Zhou, S. Yang, Yu-xi Liu, C. P. Sun, Franco Nori. 2010-01-04. Quantum Zeno switch for single-photon coherent transport. https://doi.org/10.1103/physreva.80.062109

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