Fast state tomography with optimal error bounds
Abstract
Projected least squares is an intuitive and numerically cheap technique for quantum state tomography: compute the least-squares estimator and project it onto the space of states. The main result of this paper equips this point estimator with rigorous, non-asymptotic convergence guarantees expressed in terms of the trace distance. The estimator’s sample complexity is comparable to the strongest convergence guarantees available in the literature and—in the case of the uniform POVM—saturates fundamental lower bounds. Numerical simulations support these competitive features.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 28, 2020
- Source ID
- 10.1088/1751-8121/ab8111
Entities
People
- J Kahn
- J. A. Tropp
- Mădălin Guţǎ
- R. Kueng
Organizations
- National Science Foundation
- Office of Naval Research Global