Quantum fluctuation properties of continuous-variable entangled state based on general two-mode Boson exponential quadratic operator in Fock space

Abstract

Abstract:

By virtue of the linear quantum transformation theory(LQTT), a general formula was obtained, which calculate the quantum fluctuations for bipartite entangled state of continuous variables in Fock space. Moreover, the squeezed properties of the entangled state are discussed. The relations between the state parameters are depicted by means of the linear fit, when the degree of the fluctuation and entanglement entropy reach the extremum. When the entangled state is maximally entangled, the results show that the squeezed degree is also maximal. In addition, the changing relationship between the quantum fluctuations and the quantum entanglement is acquired. The derived formula are used to calculate the fluctuation of the common two-mode squeezed vacuum state and the two-mode one-sided squeezed vacuum state as examples.

Key words: quantum optics, quantum fluctuation, linear quantum transformation theory, squeezed properties, continuous-variable entangled states

LU Jun-Zhe, LI An-Kang, MA Lei. Quantum fluctuation properties of continuous-variable entangled state based on general two-mode Boson exponential quadratic operator in Fock space[J]. J4, 2010, 27(1): 31-39.

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