Quantum properties of superpositions of oppositely squeezed states

Abstract: We investigate the quantum properties of superpositions of oppositely squeezed states, which can be regarded as Schrodinger cat states. Compared with conventional coherent-state cat states, these states exhibit distinct photon-number structures and enhanced nonclassical features. We analyze their Wigner function and quantify the entanglement generated when they are injected into a 50:50 beam splitter. For small squeezing parameters, the resulting two-mode states possess higher entanglement than pure two-mode squeezed vacuum states. We also propose a linear-optical heralding scheme that approximates this superposition of oppositely squeezed states without requiring strong Kerr nonlinearities. Our results indicate that such states are promising resources for continuous-variable quantum information processing, particularly in regimes where high non-Gaussianity and strong entanglement are desirable.