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arXiv · 2609.01373

Local Gaussian bounds on the non-destructive discrimination of two-mode squeezed states

Mi-Jung So·James Moran·Youngrong Lim·Mahn-Soo Choi·Hyukjoon Kwon
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Abstract

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.

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Mi-Jung So, James Moran, Youngrong Lim, Mahn-Soo Choi, Hyukjoon Kwon. 2026-09-01. Local Gaussian bounds on the non-destructive discrimination of two-mode squeezed states. https://arxiv.org/abs/2609.01373

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