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arXiv · 2010.00171

Lowering Helstrom Bound with non-standard coherent states

Evaldo M. F. Curado·Sofiane Faci·Jean-Pierre Gazeau·Diego Noguera
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Abstract

In quantum information processing, {using a receiver device to differentiate between two nonorthogonal states leads to a quantum error probability. The minimum possible error is} known as the Helstrom bound. In this work we study and compare quantum limits for states which generalize the Glauber-Sudarshan coherent states, like non-linear, Perelomov, Barut-Girardello, and (modified) Susskind-Glogower coherent states. For some of these, we show that the Helstrom bound can be significantly lowered and even vanish in specific regimes.

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Evaldo M. F. Curado, Sofiane Faci, Jean-Pierre Gazeau, Diego Noguera. 2020-10-01. Lowering Helstrom Bound with non-standard coherent states. https://doi.org/10.1364/josab.428637

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