On approximation of infinite-dimensional quantum channels
نویسندگان
چکیده
Abstract—We develop an approximation approach to infinite-dimensional quantum channels based on a detailed investigation of continuity properties of entropic characteristics of quantum channels and operations (trace-nonincreasing completely positive maps) as functions of a pair “channel, input state.” Obtained results are then applied to the problems of continuity of the χ-capacity as a function of a channel, strong additivity of the χ-capacity for infinite-dimensional channels, and approximating representation for the convex closure of the output entropy of an arbitrary quantum channel.
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ورودعنوان ژورنال:
- Probl. Inf. Transm.
دوره 44 شماره
صفحات -
تاریخ انتشار 2008