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arXiv · 2402.17118

Heralded single-photon source based on superpositions of squeezed states

Hiroo Azuma·William J. Munro·Kae Nemoto
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Abstract

We propose a heralded single-photon source based on injecting a superposition of oppositely squeezed states onto a beam splitter. Our superposition of squeezed states is composed of only even photon number states (the number of photons is equal to $2,6,10,...$) meaning the probability for an emitted single photon given as a heralded single-photon event is higher than what one can achieve from the usual two-mode squeezed state. This enables one to realize an enhanced heralded single-photon source. We discuss how to create this superposition of squeezed states utilizing a single-mode squeezed state and the cross-Kerr nonlinearity. Our proposed method significantly improves the probability of emitting the heralded single photon compared to spontaneous parametric down-conversion.

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Hiroo Azuma, William J. Munro, Kae Nemoto. 2024-02-27. Heralded single-photon source based on superpositions of squeezed states. https://doi.org/10.1103/physreva.109.053711

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