Chinese Physics Letters

Nonclassical Properties of Superposition of Two Coherent States Shifted in Phase by 3π/2

Muhammad Ashfaq Ahmad, Ran Zeng, Shutian Liu

Published Sep 1, 2006• 11 citations

Abstract

We consider the quantum superposition of two coherent states shifted in phase by 3π/2, |α⟩ and |− i α⟩, as well as special states that are characterized solely with respect to amplitude α. According to analysis of nonclassical properties such as oscillatory and sub-Poissonian distribution of photon numbers, photon antibunching, quadrature squeezing, and negativity of Wigner function, it is concluded that the considered superposition state is a nonclassical state. Also, the special state is found to exhibit even stronger nonclassical features when relative phase ϕ of the superposition is equal to the average photon number |α| 2 .

DOI: 10.1088/0256-307x/23/9/024

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