Mixed State Discrimination Using Optimal Control
- 24 November 2009
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 103 (22), 220503
- https://doi.org/10.1103/physrevlett.103.220503
Abstract
We present theory and experiment for the task of discriminating two nonorthogonal states, given multiple copies. We implement several local measurement schemes, on both pure states and states mixed by depolarizing noise. We find that schemes which are optimal (or have optimal scaling) without noise perform worse with noise than simply repeating the optimal single-copy measurement. Applying optimal control theory, we derive the globally optimal local measurement strategy, which outperforms all other local schemes, and experimentally implement it for various levels of noise.Keywords
Other Versions
This publication has 16 references indexed in Scilit:
- Demonstrating Heisenberg-limited unambiguous phase estimation without adaptive measurementsNew Journal of Physics, 2009
- Entanglement-free Heisenberg-limited phase estimationNature, 2007
- Optical coherent state discrimination using a closed-loop quantum measurementNature, 2007
- Quantum control of a single qubitPhysical Review A, 2007
- Quantum Kalman Filtering and the Heisenberg Limit in Atomic MagnetometryPhysical Review Letters, 2003
- Adaptive Homodyne Measurement of Optical PhasePhysical Review Letters, 2002
- Local Distinguishability of Multipartite Orthogonal Quantum StatesPhysical Review Letters, 2000
- Semiclassical Fourier Transform for Quantum ComputationPhysical Review Letters, 1996
- How to differentiate between non-orthogonal statesPhysics Letters A, 1987
- Quantum detection and estimation theoryJournal of Statistical Physics, 1969