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arXiv:0807.1028

Density matrix of the superposition of excitation on coherent states with thermal light and its statistical properties

Li-Yun Hu, Hong-Yi Fan

Published Jul 7, 2008• 0 citations
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Abstract

A beam's density matrix that is described by the superposition of excitation on coherent states with thermal noise (SECST) is presented, and its matrix elements in Fock space are calculated. The maximum information transmitted by the SECST beam is derived. It is more than that by coherent light beam and increases as the excitation photon number increases. In addition, the nonclassicality of density matrix is demonstrated by calculating its Wigner function.

DOI
10.48550/arxiv.0807.1028

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A beam's density matrix that is described by the superposition of excitation on coherent states with thermal noise (SECST) is presented, and its matrix elements in Fock space are calculated. The maximum information transmitted by the SECST beam is derived. It is more than that by coherent light beam and increases as the excitation photon number increases. In addition, the nonclassicality of density matrix is demonstrated by calculating its Wigner function.
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We investigate a free monochromatic electromagnetic field which is in the even or odd coherent state with thermal noise. The main tool in our analysis is the characteristic function. We establish an alystic formula for an arbitrary correlation function. We point out the non-classical oscillations of the photon-number distribution and find its generating function as well as the degree of purity of the field. We also examine the squeezing properties and antibunching feature. Besides, the usual quasiprobability densities are derived.