English

Design of Strict Control-Lyapunov Functions for Quantum Systems with QND Measurements

Optimization and Control 2011-08-09 v2 Systems and Control Quantum Physics

Abstract

We consider discrete-time quantum systems subject to Quantum Non-Demolition (QND) measurements and controlled by an adjustable unitary evolution between two successive QND measures. In open-loop, such QND measurements provide a non-deterministic preparation tool exploiting the back-action of the measurement on the quantum state. We propose here a systematic method based on elementary graph theory and inversion of Laplacian matrices to construct strict control-Lyapunov functions. This yields an appropriate feedback law that stabilizes globally the system towards a chosen target state among the open-loop stable ones, and that makes in closed-loop this preparation deterministic. We illustrate such feedback laws through simulations corresponding to an experimental setup with QND photon counting.

Keywords

Cite

@article{arxiv.1103.1365,
  title  = {Design of Strict Control-Lyapunov Functions for Quantum Systems with QND Measurements},
  author = {Hadis Amini and Pierre Rouchon and Mazyar Mirrahimi},
  journal= {arXiv preprint arXiv:1103.1365},
  year   = {2011}
}