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arXiv · 2511.09417

Weight-based measure of quantum memory as a universal and operational benchmark

Jinghang Zhang·Yu Luo
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Abstract

Quantum memory plays a critical role in quantum communication, sensing, and computation. However, studies on quantum memory under a unified benchmarking framework remain scarce. In this paper, we propose a weight-based quantifier as a benchmarking method to evaluate the performance advantage of quantum memory in nonlocal exclusion tasks. We establish a general lower bound for the weight-based measure of quantum memory. Moreover, this measure provides fundamental theoretical bounds for transforming a general channel into an ideal quantum memory. Finally, we present explicit calculations of the weight-based quantifier for various channels, including unitary channels, depolarizing channels, maximal replacement channels, stochastic damping channels, and erasure channels.

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Jinghang Zhang, Yu Luo. 2025-11-12. Weight-based measure of quantum memory as a universal and operational benchmark. https://doi.org/10.1103/9fj9-x3v6

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