Single-photon-subtracted squeezed vacuum state-based postselected von Neumann measurement

Abstract

This paper studies the effects of the postselected von Neumann measurement on the nonclassicality of the single-photon-subtracted squeezed vacuum (SPSSV) state. Specifically, we calculated the squeezing effect, Mandel factor, Wigner function, signal-to-noise ratio (SNR), and state distance function. We found that the postselected von Neumann measurement positively affects the SPSSV state optimization. Precisely, correctly choosing the anomalous weak value allows for optimizing the nonclassical inherent features of the SPSSV state, such as squeezing, photon statistics, and phase space distribution. Additionally, this study confirms the advantages of postselected WM in improving the SNR compared to non-postselected measurement schemes. Furthermore, a possible implementation method is proposed using optics setups. The superiority of the SPSSVS-based postselected WM in quantum state optimization can support various applications in the associated quantum information processing.