DPG Phi
Verhandlungen
Verhandlungen
DPG

Frankfurt 2006 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

Q: Quantenoptik und Photonik

Q 50: Quanteninformation IV

Q 50.4: Vortrag

Mittwoch, 15. März 2006, 14:45–15:00, HI

Unambiguous quantum parity check — •Hermann Kamermann1, Matthias Kleinmann1, Tim Meyer1, Philippe Raynal2, Norbert Lütkenhaus2, and Dagmar Bruß11Heinrich Heine Universität Düsseldorf, Theoretische Physik III — 2Universität Erlangen-Nürnberg, Institut für Theoretische Physik I

We consider the task to determine without error, whether a string consisting of non-orthogonal quantum states ψ0 and ψ1 (with a priori probabilities η0 and η1) has even or odd parity, i.e. whether it consists of an even or odd number of ψ1’s. As perfect discrimination between non-orthogonal quantum states is impossible, the measurement outcomes, even parity (FE), odd parity (FO) or “I don’t know” (F?) can occur. Bennett et al. [1] solved the task of finding the minimal error probability for the case η01, by relating it to an unambiguous state discrimination problem. We prove that the optimal measurement leads to identical failure rates for a string of 2n−1 and 2n states for η01. We investigate the generalization of this task to arbitrary a priori probabilities and its effects on the failure rates.

[1] C.H. Bennett, T. Mor, and J.A. Smolin. Phys. Rev. A, 54(4), 2675, (1996)

100% | Mobil-Ansicht | English Version | Kontakt/Impressum/Datenschutz
DPG-Physik > DPG-Verhandlungen > 2006 > Frankfurt