Title
Fidelity between one bipartite quantum state and another undergoing local unitary dynamics
Abstract
The fidelity and local unitary transformation are two widely useful notions in quantum physics. We study two constrained optimization problems in terms of the maximal and minimal fidelity between two bipartite quantum states undergoing local unitary dynamics. The problems are related to the geometric measure of entanglement and the distillability problem. We show that the problems can be reduced to semidefinite programming optimization problems. We give closed-form formulae of the fidelity when the two states are pure states, or a pure product state and the Werner state. We explain from the point of view of local unitary actions that why the entanglement in Werner states is hard to accessible. For general mixed states, we give upper and lower bounds of the fidelity using tools such as affine fidelity, channels, and relative entropy from information theory. We also investigate the power of local unitaries and the equivalence of the two optimization problems.
Year
DOI
Venue
2015
10.1007/s11128-015-1117-7
Quantum Information Processing
Keywords
DocType
Volume
Fidelity, Bipartite state, Local unitary transformation, Werner state
Journal
14
Issue
ISSN
Citations 
12
1573-1332
1
PageRank 
References 
Authors
0.75
4
3
Name
Order
Citations
PageRank
Lin Zhang114616.93
lin chen210.75
kaifeng bu310.75