2025/09/29 by Yao, Xiao-Xi, Turek, Yusuf
#FOS: Physical sciences #Quantum Physics (quant-ph)
paper · doi:10.48550/arxiv.2509.24188
We introduce a feasible protocol for generating non-Gaussian (nG) states via postselected von Neumann measurement for continuous-variable quantum information processing. The method uses a two-level system coupled to a Gaussian pointer state through an observable A with A2=\mathbbI. By operating beyond the weak-coupling regime and selecting different pointer states -- squeezed, coherent, or vacuum -- allows generation of a wide range of nG states, including squeezed cat states, two-mode entangled cat states, approximate Bell states, and a continuum of intermediate nG states with considerable success probabilities. The properties of these states are widely tunable via the postselection-induced weak value and the measurement interaction strength. We characterize the non-Gaussianity via Wigner function negativities and quantify entanglement using linear entropy and concurrence. The protocol offers a scalable route to high-purity nG state engineering.