Signatures of entanglement in an optical tomogram

TL;DR

This paper demonstrates that entanglement signatures can be directly observed in optical tomograms of entangled states generated by a beam splitter, without needing to reconstruct the density matrix.

Contribution

It introduces a method to identify entanglement signatures directly in optical tomograms, simplifying entanglement detection in quantum optical systems.

Findings

Distinct optical tomogram features indicate entanglement.

Optical tomograms differ based on quadrature measurements in entangled states.

Photon number statistics support the tomogram observations.

Abstract

We theoretically study the optical tomography 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 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.