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Journal of Atomic and Molecular Physics

Squeezing properties of two-mode excitons in a system of two coupled quantum dots and cavity QED

Shao-Hua Xiang

Published Jan 1, 2007• 0 citations

Abstract

Squeezing properties of two-mode excitons in a system of two coupled quantum dots and cavity QED is investigated.The effect of the different initial cavity field states on two-mode excitons normal squeezing and sum squeezing has been discussed.A conclusion has also been obtained through calculating.It is that when the cavity field is initial prepared in coherent states,two-mode excitons normal squeezing do not exist as well as the sum squeezing.It indicates that the two quadrature components of the excitons amplitude possess the same quantum fluctuation.However,in the case that cavity field is in the vacuum squeezed state,no matter how normal squeezing or sum squeezing,either of the two quadrature component of the excitons amplitude are always of squeezing,it implies that quantum noise can be effective restrained in the case.Otherwise,the maximum squeezing in both situations is determined by the initial cavity field squeezing factor r.After comparing normal squeezing and sum squeezing,we can find that two-mode excitons normal squeezing is larger than sum squeezing.

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