Physics – Quantum Physics
Scientific paper
2011-02-04
J. Phys. A: Math. Theor. 44, 495303 (2011)
Physics
Quantum Physics
Minor corrections and updates since v1. 16 pages, 1 figure
Scientific paper
10.1088/1751-8113/44/49/495303
We provide new results for computing and comparing the quantum gate fidelity of quantum channels via their Choi matrices. We extend recent work that showed there exist non-dual pairs of quantum channels with equal gate fidelity by providing an explicit characterization of all such channels. We use our characterization to show that when the dimension is 2 (or 3, under slightly stronger hypotheses), the gate fidelity of two channels is equal if and only if their difference equals the difference of some unital map and its dual -- a fact that has been shown to be false when the dimension is 4 or larger. We also present a formula for the minimum gate fidelity of a channel in terms of a well-studied norm on a compression of its Choi matrix. As a consequence, several new ways of bounding and approximating the minimum gate fidelity follow, including a simple semidefinite program to compute it for qubit channels.
Johnston Nathaniel
Kribs David W.
No associations
LandOfFree
Quantum Gate Fidelity in Terms of Choi Matrices 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 Quantum Gate Fidelity in Terms of Choi Matrices, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Quantum Gate Fidelity in Terms of Choi Matrices will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-491953