Second order asymptotics of visible mixed quantum source coding via universal codes

Understand

The simplest example of a quantum information source with memory is a mixed source which emits signals entirely from one of two memoryless quantum sources with given a priori probabilities.

• Considering a mixed source consisting of a general one-parameter family of memoryless sources, we derive the second order asymptotic rate for fixed-length visible source coding.
• Furthermore, we specialize our main result to a mixed source consisting of two memoryless sources.
• Our results provide the first example of second order asymptotics for a quantum information-processing task employing a resource with memory.