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On quantum coding for ensembles of mixed states

Howard Barnum·Carlton M. Caves·Christopher A. Fuchs·Richard Jozsa·Benjamin W. Schumacher
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Abstract

We consider the problem of optimal asymptotically faithful compression for ensembles of mixed quantum states. Although the optimal rate is unknown, we prove upper and lower bounds and describe a series of illustrative examples of compression of mixed states. We also discuss a classical analogue of the problem.

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Howard Barnum, Carlton M. Caves, Christopher A. Fuchs, Richard Jozsa, Benjamin W. Schumacher. 2000-08-04. On quantum coding for ensembles of mixed states. https://doi.org/10.1088/0305-4470%2F34%2F35%2F304

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