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arXiv · 2003.06302

Optimal quantum phase estimation with generalized multi-component Schrodinger cat states

Seung-Woo Lee·Su-Yong Lee·Jaewan Kim
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Abstract

In this paper, we are interested in detecting the presence of a nearby phase-sensitive object, where traveling light works out under a low-photon loss rate. Here we investigate the optimal quantum phase estimation with generalized multi-component Schrodinger cat states. In addition, we show the optimal conditions of the generalized multi-component cat states for the phase estimation in a lossless scenario. We then demonstrate that the generalized multi-component cat states can beat the performances of the NOON and two-mode squeezed vacuum states in the presence of small loss, while maintaining the quantum advantage over the standard quantum limit, attainable by coherent states. Finally, we propose a generation scheme of the entangled multi-component cat states with current or near-term optical technologies.

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Seung-Woo Lee, Su-Yong Lee, Jaewan Kim. 2020-03-13. Optimal quantum phase estimation with generalized multi-component Schrodinger cat states. https://doi.org/10.1364/josab.393200

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