Quantum-state disturbance versus information gain: Uncertainty relations for quantum information
Abstract
When an observer wants to identify a quantum state, which is known to be one of a given set of nonorthogonal states, the act of observation causes a disturbance to that state. We investigate the trade-off between the information gain and that disturbance. This issue has important applications in quantum cryptography. The optimal detection method, for a given tolerated disturbance, is explicitly found in the case of two equiprobable nonorthogonal pure states.
- Publication:
-
Physical Review A
- Pub Date:
- April 1996
- DOI:
- 10.1103/PhysRevA.53.2038
- arXiv:
- arXiv:quant-ph/9512023
- Bibcode:
- 1996PhRvA..53.2038F
- Keywords:
-
- 03.65.Bz;
- Quantum Physics
- E-Print:
- 20 pages, standard LaTeX, four png figures (also available from the authors: peres@photon.technion.ac.il and cfuchs@tangelo.phys.unm.edu)