Geometric phase in entangled systems: A single-neutron interferometer experiment

Journal Article · Thu Apr 15 00:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.81.042113· OSTI ID:21408563

Sponar, S; Klepp, J; Loidl, R; Durstberger-Rennhofer, K; Badurek, G; Hasegawa, Y ^[1]; Filipp, S ^[2]; Bertlmann, R A ^[3]; Rauch, H ^[1]

---

1. Atominstitut der Oesterreichischen Universitaeten, A-1020 Vienna (Austria)
2. Department of Physics, Eidgenoessische Technische Hochschule Zuerich, Schafmattstrasse 16, CH-8093 Zurich (Switzerland)
3. Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna (Austria)

The influence of the geometric phase on a Bell measurement, as proposed by Bertlmann et al. [Phys. Rev. A 69, 032112 (2004)] and expressed by the Clauser-Horne-Shimony-Holt (CHSH) inequality, has been observed for a spin-path-entangled neutron state in an interferometric setup. It is experimentally demonstrated that the effect of geometric phase can be balanced by a change in Bell angles. The geometric phase is acquired during a time-dependent interaction with a radiofrequency field. Two schemes, polar and azimuthal adjustment of the Bell angles, are realized and analyzed in detail. The former scheme yields a sinusoidal oscillation of the correlation function S, dependent on the geometric phase, such that it varies in the range between 2 and 2{radical}(2) and therefore always exceeds the boundary value 2 between quantum mechanic and noncontextual theories. The latter scheme results in a constant, maximal violation of the Bell-like CHSH inequality, where S remains 2{radical}(2) for all settings of the geometric phase.

• OSTI ID: 21408563
• Journal Information: Physical Review. A, Vol. 81, Issue 4; Other Information: DOI: 10.1103/PhysRevA.81.042113; (c) 2010 The American Physical Society; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CORRELATION FUNCTIONS
GEOMETRY
INTERACTIONS
INTERFEROMETERS
NEUTRONS
OSCILLATIONS
QUANTUM ENTANGLEMENT
RADIOWAVE RADIATION
SPIN
TIME DEPENDENCE
ANGULAR MOMENTUM
BARYONS
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
FERMIONS
FUNCTIONS
HADRONS
MATHEMATICS
MEASURING INSTRUMENTS
NUCLEONS
PARTICLE PROPERTIES
RADIATIONS