Physics – Quantum Physics
Scientific paper
2003-05-29
Phys. Rev. A 68, 042113 (2003)
Physics
Quantum Physics
8 pages, no figures. Accepted for publication on Phys. Rev. A
Scientific paper
10.1103/PhysRevA.68.042113
Quantum operations (QO) describe any state change allowed in quantum mechanics, such as the evolution of an open system or the state change due to a measurement. We address the problem of which unitary transformations and which observables can be used to achieve a QO with generally different input and output Hilbert spaces. We classify all unitary extensions of a QO, and give explicit realizations in terms of free-evolution direct-sum dilations and interacting tensor-product dilations. In terms of Hilbert space dimensionality the free-evolution dilations minimize the physical resources needed to realize the QO, and for this case we provide bounds for the dimension of the ancilla space versus the rank of the QO. The interacting dilations, on the other hand, correspond to the customary ancilla-system interaction realization, and for these we derive a majorization relation which selects the allowed unitary interactions between system and ancilla.
Buscemi Francesco
D'Ariano Giacomo M.
Sacchi Massimiliano Federico
No associations
LandOfFree
Physical realizations of quantum operations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Physical realizations of quantum operations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Physical realizations of quantum operations will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-607510