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arXiv:2512.15095

Quantum data hiding with two-qubit separable states

Donghoon Ha, Jeong San Kim

quant-phSubmitted Dec 17, 2025• Announced Dec 18, 2025• 0 citations
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Abstract

We consider the discrimination of two-party quantum states and provide a quantum data-hiding scheme using two-qubit separable states. We first provide a bound on the optimal local discrimination of two-party quantum states, and establish a sufficient condition under which a two-party quantum state ensemble can be used to construct a data-hiding scheme. We illustrate this condition with examples of two-qubit state ensembles consisting of two orthogonal separable states. As our data-hiding scheme can be implemented with separable states of the lowest possible dimension, its practical realization becomes significantly more attainable.

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9 pages, 1 figure

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