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arXiv · 1609.08584

Asymmetric de Finetti Theorem for Infinite-dimensional Quantum Systems

Murphy Yuezhen Niu
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Abstract

The de Finetti representation theorem for continuous variable quantum system is first developed to approximate an N-partite continuous variable quantum state with a convex combination of independent and identical subsystems, which requires the original state to obey permutation symmetry conditioned on successful experimental verification on k of N subsystems. We generalize the de Finetti theorem to include asymmetric bounds on the variance of canonical observables and biased basis selection during the verification step. Our result thereby enables application of infinite-dimensional de Finetti theorem to situations where two conjugate measurements obey different statistics, such as the security analysis of quantum key distribution protocols based on squeezed state against coherent attack.

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Murphy Yuezhen Niu. 2016-09-27. Asymmetric de Finetti Theorem for Infinite-dimensional Quantum Systems. https://arxiv.org/abs/1609.08584

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