Berlin 2005 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
Q: Quantenoptik und Photonik
Q 42: Quanteninformation II
Q 42.8: Talk
Tuesday, March 8, 2005, 15:45–16:00, HU Audimax
Detecting entanglement with the stabilizer formalism — •Geza Toth1 and Otfried Gühne2 — 1Theoretical Division, Max Planck Institute for Quantum Optics, Hans Kopfermann Str. 1, D 85748 Garching, Germany — 2Institut für Quantenoptik und Quanteninformation,Österreichische Akademie der Wissenschaften,Innsbruck A-6020, Austria
Stabilizer theory plays a central role in error correction and fault tolerant quantum computation. We investigate how it can be used for constructing sufficient conditions for entanglement. All our criteria detect states close to Greenberger-Horne-Zeilinger (GHZ) states, cluster and graph states. GHZ states have intensively been studied as maximally entangled states. Cluster and graph states raised a lot of interest, since they allow for measurement based quantum computing. They naturally arise in spin chains, and their entanglement is more immune to noise than that of the GHZ state.
In this talk we will derive entanglement conditions using the stabilizer theory. These conditions will be presented in the form of entanglement witness operators. It is important from the experimental point of view that our constructions are robust against noise and they make it possible for detecting multi-qubit entanglement with the minimal two local measurement settings.
Beside entanglement witnesses, nonlinear entanglement conditions will also be constructed using the stabilizer theory. We also discuss interesting connections between the witnesses and some Bell inequalities. For further details, please see quant-ph/0405165.