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arXiv · 2112.02312

Indirect Measurement for Optimal Quantum Communication Enhanced by Binary Non-standard Coherent States

Min Namkung·Jeong San Kim
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Abstract

It is well known that the Helstrom bound can be improved by generalizing the form of a coherent state. Thus, designing a quantum measurement achieving the improved Helstrom bound is important for novel quantum communication. In the present article, we analytically show that the improved Helstrom bound can be achieved by a projective measurement composed of orthogonal non-standard Schr\"{o}dinger cat states. Moreover, we numerically show that the improved Helstrom bound can be nearly achieved by an indirect measurement based on the Jaynes-Cummings model. As the Jaynes-Cummings model describes an interaction between a light and a two-level atom, we emphasize that the indirect measurement considered in this article has potential to be experimentally implemented.

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Min Namkung, Jeong San Kim. 2021-12-04. Indirect Measurement for Optimal Quantum Communication Enhanced by Binary Non-standard Coherent States. https://doi.org/10.1364/josab.450647

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