Chinese Physics

Entropy squeezing of a moving atom and control of noise of the quantum mechanical channel via the two-photon process

Bingju Zhou, Xiaojuan Liu, Qingping Zhou, Liu Ming-Wei

Published Jan 24, 2007• 10 citations

Abstract

Based on the quantum information theory, we have investigated the entropy squeezing of a moving two-level atom interacting with the coherent field via the quantum mechanical channel of the two-photon process. The results are compared with those of atomic squeezing based on the Heisenberg uncertainty relation. The influences of the atomic motion and field-mode structure parameter on the atomic entropy squeezing and on the control of noise of the quantum mechanical channel via the two-photon process are examined. Our results show that the squeezed period, duration of optimal entropy squeezing of a two-level atom and the noise of the quantum mechanical channel can be controlled by appropriately choosing the atomic motion and the field-mode structure parameter, respectively. The quantum mechanical channel of two-photon process is an ideal channel for quantum information (atomic quantum state) transmission. Quantum information entropy is a remarkably accurate measure of the atomic squeezing.

DOI: 10.1088/1009-1963/16/2/023

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