Repeated Quantum Non-Demolition Measurements: Convergence and Continuous Time Limit

  title={Repeated Quantum Non-Demolition Measurements: Convergence and Continuous Time Limit},
  author={M. Bauer and T. Benoist and D. Bernard},
  journal={Annales Henri Poincar{\'e}},
We analyze general enough models of repeated indirect measurements in which a quantum system interacts repeatedly with randomly chosen probes on which von Neumann direct measurements are performed. We prove, under suitable hypotheses, that the system state probability distribution converges after a large number of repeated indirect measurements, in a way compatible with quantum wave function collapse. We extend this result to mixed states and we prove similar results for the system density… Expand
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