Physics – Quantum Physics
Scientific paper
2011-06-23
Physics
Quantum Physics
22 pages, 12 figures
Scientific paper
Pointer states are long-lasting high-fidelity states in open quantum systems. We show how any pure state in a non-Markovian open quantum system can be made to behave as a pointer state by suitably engineering the coupling to the environment via open-loop periodic control. Engineered pointer states are constructed as approximate fixed points of the controlled open-system dynamics, in such a way that they are guaranteed to survive over a long time with a fidelity determined by the relative precision with which the dynamics is engineered. We provide quantitative minimum-fidelity bounds by identifying symmetry and ergodicity conditions that the decoherence-inducing perturbation must obey in the presence of control, and develop explicit pulse sequences for engineering any desired set of orthogonal states as pointer states. These general control protocols are validated through exact numerical simulations as well as semi-classical approximations in realistic single and two qubit dissipative systems. We also examine the role of control imperfections, and show that while pointer-state engineering protocols are highly robust in the presence of systematic pulse errors, the latter can also lead to unintended pointer-state generation in dynamical decoupling implementations, explaining the initial-state selectivity observed in recent experiments.
Dobrovitski Viatcheslav V.
Khodjasteh Kaveh
Viola Lorenza
No associations
LandOfFree
Pointer States via Engineered Dissipation 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 Pointer States via Engineered Dissipation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pointer States via Engineered Dissipation will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-470520