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Communications in Theoretical Physics

Photon-modulated displaced thermal states: negativity and non-Gaussianity

Wei Wu, Yong Fang, Peng Fu

Published Oct 22, 2024• 1 citation
Publisher

Abstract

Abstract In this paper, we propose a new non-Gaussian quantum state, termed the photon-modulated displaced thermal state (DTS). Using the operator ordering method, we obtain the normal ordering product of its density operator and then investigate its normalization, the negativity of its Wigner function and its non-Gaussianity.
DOI
10.1088/1572-9494/ad89ad

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We investigate how displaced thermal states (DTSs) evolve in a laser channel. Remarkably, the initial DTS, an example of a mixed state, still remains mixed and thermal. At long times, they finally decay to a highly classical thermal field only related to the laser parameters κ and g . The normal ordering product of density operator of the DTS in the laser channel leads to obtaining the analytical time-evolution expressions of the photon number, Wigner function, and von Neumann entropy. Also, some interesting results are presented via numerically investigating these explicit time-dependent expressions.
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