Squeezed Photon States

Qingyi Yang

Photon-added squeezed vacuum states were fabricated by act inverse operator of Boson annihilation operator ~(-1) and Boson creation operator ~+ on the squeezed vacuum states first.Then the squeezing properties of the photon-added squeezed vacuum states are discussed.The results show that only the photon-added squeezed state which was acted on ~+ can appear squeezing effects,but was acted on ~(-1) did not.The squeezing range have relation with the squeezing parameter η.So the squeezing properties of the photon-added squeezed vacuum states have closed relation with ~(-1) and ~+.

Kevin Zelaya, Sanjib Dey, Véronique Hussin

Pierre Meystre, Murray Sargent

Zhen Wang, Xiang‐Gao Meng, Heng-Mei Li +1 more

We put forward the photon-added squeezing-enhanced thermal states (PASETS) theoretically by adding photon to the squeezed enhancing thermal states (SETS) repeatedly. Based on the normally ordered density operator of PASETS, we investigate the nonclassical behavior of the PASETS by evaluating, both analytically and numerically, Mandel's Q-parameter, photon-number distribution (PND), and Wigner function (WF). It is found that smaller squeezing parameter r and thermal photon number nc can lead to more chance of the appearance of sub-Poissonian statistics. And it is shown that the PND of PASETS exhibit more remarkable oscillations than that of SETS in stronger squeezing case. The WF exhibit partial negativity in phase space and the squeezing parameter r can result in both squeezing and rotating effect. By investigating the fidelity between PASETS and SETS shows that the fidelity tender to steady values in the high value of squeezing parameter or thermal photon number. In addition, the decoherence effect on the PASETS is examined by the time-evolution of the analytical WF in thermal channel. The results show that the PASETS shall lose nonclassicality and non-Gaussianity and reduce to classical states with Gaussian distribution after sufficient time interaction with the thermal noise. And larger photon-added number or thermal photon number shall render shorter decoherence time.

Chon‐Fai Kam, Wei-Min Zhang, D.H. Feng

Hong-Yi Fan, Liyun Hu, Xue-xiang Xu

By converting the photon-subtracted squeezed state (PSSS) to a squeezed Hermite-polynomial excitation state we find that the normalization factor of PSSS is an m-order Legendre polynomial of the squeezing parameter, where m is the number of subtracted photons. Some new relations about the Legendre polynomials are obtained by this analysis. We also show that the PSSS can also be treated as a Hermite-polynomial excitation on squeezed vacuum state.