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arXiv · 1902.10181

Mach-Zehnder interferometer with quantum beamsplitters

Nelson Almeida·Thiago Werlang·Daniel Valente
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Abstract

A one-dimensional waveguide enables a single two-level emitter to route the propagation of a single photon, as to provide a quantum mirror or a quantum beamsplitter. Here we present a fully-quantum Mach-Zehnder interferometer (QMZ) for single-photon pulses comprised of two quantum beamsplitters. We theoretically show how nonlinearities of the QMZ due to photon-emitter detunings and to the spectral linewidth of the pulse contribute to the versatility of the device with respect to the classical-beamsplitters scenario. We employ a quantum dynamics framework to obtain analytical expressions for the photodetection probabilities and prove, in the monochromatic regime, the equivalence with a transfer-matrix approach.

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Nelson Almeida, Thiago Werlang, Daniel Valente. 2019-02-26. Mach-Zehnder interferometer with quantum beamsplitters. https://doi.org/10.1364/josab.36.003357

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