arXiv:1505.02698 · Journal of the Optical Society of America B

Signatures of entanglement in an optical tomogram

M. Rohith, C. Sudheesh

Published Jan 5, 2016• 24 citations

Abstract

We theoretically study the optical tomograms of maximally entangled states generated at the output modes of a beam splitter. We consider even and odd coherent states in one of the input modes and vacuum state in the other input mode of the beam splitter. We have shown that the signatures of entanglement can be observed directly in the single-mode optical tomogram of the state without reconstructing the density matrix of the system. Two distinct types of optical tomograms are observed in any one of the output modes of the beam splitter based on the quadrature measurement in the other output mode if the output modes are entangled. The different features shown by the optical tomograms are verified by investigating the photon-number statistics of the corresponding state. We analyze the effect of decoherence on the optical tomograms of the entangled states.

DOI: 10.1364/josab.33.000126

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