Statistical signatures of multimode single-photon added and subtracted states of light

TL;DR

This paper derives multimode statistical signatures for non-Gaussian states created by photon addition or subtraction, analyzing their properties, entanglement, and the effects of impurities on their quantum features.

Contribution

It introduces multimode truncated correlations as signatures and provides a full analysis of the Wigner function and entanglement in photon-added/subtracted states.

Findings

Derived multimode correlations as signatures of non-Gaussian states

Analyzed the impact of impurities on Wigner function negativity

Explored entanglement generation through photon subtraction/addition

Abstract

The addition or subtraction of a photon from a Gaussian state of light is a versatile and experimentally feasible procedure to create non-Gaussian states. In multimode setups, these states manifest a wide range of phenomena when the photon is added or subtracted in a mode-tunable way. In this contribution, we derive the truncated correlations, which are multimode generalisations of cumulants, between quadratures in different modes as statistical signatures of these states. These correlations are then used to obtain the full multimode Wigner function, the properties of which are subsequently studied. In particular we investigate the effect of impurity in the subtraction or addition process, and evaluate its impact on the negativity of the Wigner function. Finally, we elaborate on the generation of inherent entanglement through subtraction or addition of a photon from a pure squeezed vacuum.