Computing Quantum Channel Capacities

The capacity of noisy quantum channels characterizes the highest rate at which information can be reliably transmitted and it is therefore practical as well fundamental importance. Capacities classical are computed using alternating optimization schemes, called Blahut-Arimoto algorithms. In this work, we generalize algorithms to setting. particular, give efficient iterative schemes compute with input output, less channels, thermodynamic entanglement-assisted channels. We rigorous a priori posteriori bounds on estimation error by employing entropy inequalities demonstrate fast convergence our in numerical experiments.