Quantum state tomography via compressed sensing.

  title={Quantum state tomography via compressed sensing.},
  author={David Gross and Yi-Kai Liu and Steven T. Flammia and Stephen Becker and Jens Eisert},
  journal={Physical review letters},
  volume={105 15},
We establish methods for quantum state tomography based on compressed sensing. These methods are specialized for quantum states that are fairly pure, and they offer a significant performance improvement on large quantum systems. In particular, they are able to reconstruct an unknown density matrix of dimension d and rank r using O(rdlog²d) measurement settings, compared to standard methods that require d² settings. Our methods have several features that make them amenable to experimental… 

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