Lower bound on phase noise of classical states

Mark Hillery

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arXiv · 2309.08450

Lower bound on phase noise of classical states

Mark Hillery

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Abstract

An uncertainty relation for the number and phase of a single-mode field state is derived. It is then used to find a lower bound on the phase noise of a classical state. Any state that violates this condition is nonclassical. An example of such a nonclassical state is presented. Because a nonclassical state can have less phase noise than a classical state with the same average photon number, nonclassical states can play a role in the measurement of small phase shifts.

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Mark Hillery. 2023-09-15. Lower bound on phase noise of classical states. https://arxiv.org/abs/2309.08450

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