Abstract
We investigate nonclassicality and decoherence of field states generated with the non-Gaussian operation of photon addition to a two-mode squeezed thermal state (TSTS) using the normally ordered density operator of the photon-added TSTS (PTSTS). The normalization factor of the PTSTS is just a Jacobi polynomial of the squeezing parameter and the average photon number of the thermal field. We show that the fields in such states exhibit remarkable quantum features, such as sub-Poissonian photon statistics, the anti-bunching effect, and photon-number distribution. The nonclassicality is discussed in phase space based on the partial negativity of the Wigner function (WF) with two-variable Hermite polynomials. The results show that the non-Gaussian WF always exhibits the quantum interference structure caused by the two-mode squeezing operation and has some negative regions for any value of , , and the photon-addition numbers , . In addition, the effect of decoherence on the PTSTS in the thermal channel is studied by analytically deriving the time-evolution WF. We find that the WF becomes Gaussian (corresponding to a classical thermal state) at long times, losing its nonclassicality as a result of decoherence, and a larger (or ) leads to a longer decoherence time .
©2012 Optical Society of America
Full Article | PDF ArticleMore Like This
Li-Yun Hu and Zhi-Ming Zhang
J. Opt. Soc. Am. B 29(4) 529-537 (2012)
Li-Yun Hu, Fang Jia, and Zhi-Ming Zhang
J. Opt. Soc. Am. B 29(6) 1456-1464 (2012)
Xiang-guo Meng, Zhen Wang, Hong-yi Fan, and Ji-suo Wang
J. Opt. Soc. Am. B 29(11) 3141-3149 (2012)