Journal of the Optical Society of America B
Statistical properties of coherent photon-added two-mode squeezed vacuum and its inseparability
Liyun Hu, Zhiming Zhang
Abstract
We investigate the statistical properties and inseparability of the field states generated by any order nonlocal coherent photon addition (CPA) to the two-mode squeezed vacuum (TMSV). It is shown that the normalization factor of the CPA-TMSV is a Legendre polynomial, a compact expression. The statistical properties are discussed according to the analytical expressions of cross-correlation function, antibunching effect, and the negativity of its Wigner function. The inseparability is presented by using Shchukin–Vogel criteria and the Einstein–Podolsky–Rosen correlation. It is found that the symmetrical CPA-TMSV may possess stronger correlation than the single-mode photon-addition case. The lower bound of entanglement of the CPA-TMSV is considered, which indicates the logarithmic negativity is invalid for verifying the entanglement when the squeezing parameter is less than a threshold value, a period function of π/2. In addition, quantum teleportation is examined, which shows that asymmetric photon-added TMSV may be more useful for teleportation than the symmetric case.