Reliability Function of Classical-Quantum Channels
<|reference_start|>Reliability Function of Classical-Quantum Channels: We study the reliability function of general classical-quantum channels, which describes the optimal exponent of the decay of decoding error when the communication rate is below the capacity. As main result, we prove a lower bound, in terms of the quantum Renyi information in Petz's form, for the reliability function. This resolves Holevo's conjecture proposed in 2000, a long-standing open problem in quantum information theory. It turns out that the obtained lower bound matches the upper bound derived by Dalai in 2013, when the communication rate is above a critical value. Thus we have determined the reliability function in this high-rate case. Our approach relies on Renes' breakthrough made in 2022, which relates classical-quantum channel coding to that of privacy amplification, as well as our new characterization of the channel Renyi information.<|reference_end|>
@article{li2024reliability,
    title={Reliability Function of Classical-Quantum Channels},
    author={Ke Li, Dong Yang},
    journal={arXiv preprint arXiv:2407.12403},
    year={2024},
    archivePrefix={arXiv},
    eprint={2407.12403},
    primaryClass={quant-ph cs.IT math.IT}
}