5 papers
Onset of superactivation of quantum capacity
Marco Parentin, Bjarne Bergh, Nilanjana Datta +1
Superactivation of quantum capacity is the phenomenon whereby two quantum channels, each with zero quantum capacity, can exhibit a strictly positive capacity when used in tandem. I…
Strong converse bounds on the classical identification capacity of the qubit depolarizing channel
Liuhang Ye, Bjarne Bergh, Nilanjana Datta
A strong converse bound for the classical identification capacity of a quantum channel is an upper bound on the asymptotic identification rate of classical messages sent through th…
Generalized Quantum Stein's Lemma and Reversibility of Quantum Resource Theories for Classical-Quantum Channels
Bjarne Bergh, Nilanjana Datta, Anirudh Khaitan
We extend the recent proof of the Generalized Quantum Stein's Lemma by Hayashi and Yamasaki [arXiv:2408.02722] to classical-quantum (c-q) channels. We analyze the composite hypothe…
An invitation to the sample complexity of quantum hypothesis testing
Hao-Chung Cheng, Nilanjana Datta, Nana Liu +3
Quantum hypothesis testing (QHT) has been traditionally studied from the information-theoretic perspective, wherein one is interested in the optimal decay rate of error probabiliti…
Robustness of Fixed Points of Quantum Channels and Application to Approximate Quantum Markov Chains
Robert Salzmann, Bjarne Bergh, Nilanjana Datta
Given a quantum channel and a state which satisfy a fixed point equation approximately (say, up to an error ), can one find a new channel and a state, which are respec…