ua nt - p h / 03 02 18 0 v 2 1 6 D ec 2 00 3 Subspace preserving completely positive maps
نویسنده
چکیده
A class of quantum channels and completely positive maps (CPMs) are introduced and investigated. These, which we call subspace preserving (SP) CPMs has, in the case of trace preserving CPMs, a simple interpretation as those which preserve probability weights on a given orthogonal sum decomposition of the Hilbert space of a quantum system. Several equivalent characterizations of SP CPMs are proved and an explicit construction of all SP CPMs, is provided. For a subclass of the SP channels a construction in terms of joint unitary evolution with an ancilla system, is presented. PACS numbers: 03.65.-w, 03.67.-a
منابع مشابه
ua nt - p h / 03 02 18 0 v 1 2 5 Fe b 20 03 Subspace preserving completely positive maps
A class of quantum channels and completely positive maps (CPMs) are introduced and investigated. These, which we call subspace preserving (SP) CPMs has, in the case of trace preserving CPMs, a simple interpretation as those which preserve probability weights on a given orthogonal sum decomposition of the Hilbert space of a quantum system. Several equivalent characterizations of SP CPMs are prov...
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تاریخ انتشار 2003