Entropy squeezing of the field interacting with a nearly degenerate V-type three-level atom
Zhu Shi-Ninga, Zhou Qing-Chunb
a State Key Laboratory of Solid State Microstructure, Nanjing University, Nanjing 210093, China; b State Key Laboratory of Solid State Microstructure, Nanjing University, Nanjing 210093, China; Department of Mathematics and Physics, Jiangsu University of Science and Technology, Zhenjiang 212003, China
Abstract The position- and momentum-entopic squeezing properties of the optical field in the system of a nearly degenerate three-level atom interacting with a single-mode field are investigated. Calculation results indicate that when the field is initially in the vacuum state, it may lead to squeezing of the position entropy or the momentum entropy of the field if the atom is prepared properly. The effects of initial atomic state and the splitting of the excited levels of the atom on field entropies are discussed in this case. When the initial field is in a coherent state, we find that position-entropy squeezing of the field is present even if the atom is prepared in the ground state. By comparing the variance squeezing and entropy squeezing of the field we confirm that entropy is more sensitive than variance in measuring quantum fluctuations.
Received: 07 April 2004
Revised: 05 July 2004
Published: 02 March 2005