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arXiv · 2512.15095

Quantum data hiding with two-qubit separable states

Donghoon Ha·Jeong San Kim
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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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Donghoon Ha, Jeong San Kim. 2025-12-17. Quantum data hiding with two-qubit separable states. https://arxiv.org/abs/2512.15095

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