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arXiv · 2011.00990

Sensing Single Photon in a Cat State

Arman·Gargi Tyagi·Prasanta K. Panigrahi
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Abstract

The cat state is shown to `store' a single photon through the superposition of its orthogonal counterpart with itself, and an excited oscillator state. Photon addition leads to a $\pi $ phase shift at origin in the observed phase space interference of the Wigner function, which also displays negativity, controlled by the average photon number ($|\alpha|^2$) of coherent states comprising the cat state. The maxima and minima of the sub-Planck tiles in the phase space of the kitten state are interchanged after photon addition, leading to their orthogonality. Interestingly, photon addition to Yurke-Stoler state characterized by Poissonian statistics leads to a sub-Poissonian distribution.

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Arman, Gargi Tyagi, Prasanta K. Panigrahi. 2020-10-30. Sensing Single Photon in a Cat State. https://doi.org/10.1364/ol.415713

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