Typical measurement setups in quantum systems are destructive, meaning that states are irretrievably altered after measurement. In this work, we analyse non-destructive discrimination of two two-mode squeezed vacuum states using local Gaussian measurements. We investigate a tradeoff relation between the success probability of discrimination and the fidelity of the resulting state with the initial state, and construct a protocol given by local Gaussian measurements, which is optimal within our numerically explored class. We also extend to the case where we allow for additional pre-shared entanglement, and show that this regime allows us to exceed the standard local Gaussian bound for the fidelity-success probability tradeoff. Our work provides a natural extension of the tradeoff between information gain and disturbance in entangled-state discrimination, previously established for finite-dimensional quantum systems, to infinite-dimensional continuous-variable systems.
We present a theoretical study on the generation and nonclassical properties of hybrid squeezed states (HSS), a class of engineered quantum states with enhanced quantum features. Using a modified beam splitter-Kerr medium scheme, we construct superpositions of squeezed vacuum and two-photon-added squeezed states, pro...
Mohammad Bohloul, Jia-Xin Peng, M. Amazioug et al.· Chinese Physics B· 0 citations
Quantum Fisher Information (QFI), which sets the fundamental bound on parameter estimation precision via the quantum Cramér-Rao inequality, is investigated for a general single-mode Gaussian state before and after teleportation. Using a two-mode squeezed vacuum state as a shared entanglement resource between Alice and...
P. Mahmoudi, Somayeh Mehrabankar, A. Isar· Quantum Information Processi...· 0 citations
Quantifying nonclassicality in continuous-variable systems remains a fundamental problem in quantum information science. The Tsirelson probability, central to the Tsirelson precession protocol, is defined as the average probability that a precessing quadrature yields a positive outcome when measured at $K$ equally spac...
Can entangled noise erase entanglement more efficiently than separable noise? Standard robustness restricts the added noise to separable states; generalized robustness allows any state. We prove that the two costs coincide for every two-qubit state and give an explicit full-rank qubit--qutrit state with a strict gap. P...
Xiao-Ke Wang, Zi-Yuan Liu, Ming-Yang Li et al.· 0 citations
We search a simplest and minimal way to determine whether a given quantum system is entangled or separable. For this end, we propose binary correlation measurements in which restricted knowledge of only zero or non-zero correlations is available. We consider the concrete investigation on a pure state for two particles,...
T. Ohira· International Journal of Qua...· 0 citations