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arXiv · 2509.14852

On Finite-Blocklength Noisy Classical-Quantum Channel Coding With Amplitude Damping Errors

Tamás Havas·Hsuan-Yin Lin·Eirik Rosnes·Ching-Yi Lai
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Abstract

We investigate practical finite-blocklength classical-quantum channel coding over the quantum amplitude damping channel (ADC), aiming to transmit classical information reliably through quantum outputs. Our findings indicate that for any finite blocklength, a naive (uncoded) approach fails to offer any advantage over the ADC. Instead, sophisticated encoding strategies that leverage both classical error-correcting codes and quantum input states are crucial for realizing quantum performance gains at finite blocklengths.

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Tamás Havas, Hsuan-Yin Lin, Eirik Rosnes, Ching-Yi Lai. 2025-09-18. On Finite-Blocklength Noisy Classical-Quantum Channel Coding With Amplitude Damping Errors. https://arxiv.org/abs/2509.14852

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