## Quantum state discrimination

Advances in Optics and Photonics, Vol. 1, Issue 2, pp. 238-278 (2009)

http://dx.doi.org/10.1364/AOP.1.000238

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### Abstract

It is a fundamental consequence of the superposition principle for quantum states that there must exist nonorthogonal states, that is, states that, although different, have a nonzero overlap. This finite overlap means that there is no way of determining with certainty in which of two such states a given physical system has been prepared. We review the various strategies that have been devised to discriminate optimally between nonorthogonal states and some of the optical experiments that have been performed to realize these.

© 2009 Optical Society of America

**ToC Category:**

Quantum Optics

**History**

Original Manuscript: October 10, 2008

Revised Manuscript: December 10, 2008

Manuscript Accepted: December 11, 2008

Published: February 11, 2009

**Virtual Issues**

(2009) *Advances in Optics and Photonics*

**Citation**

Stephen M. Barnett and Sarah Croke, "Quantum state discrimination," Adv. Opt. Photon. **1**, 238-278 (2009)

http://www.opticsinfobase.org/aop/abstract.cfm?URI=aop-1-2-238

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