https://doi.org/10.1140/epjd/e2014-50349-2
Regular Article
Entanglement and the Born-Oppenheimer approximation in an exactly solvable quantum many-body system
1
Instituto Carlos I de Física Teórica y Computacional and
Departamento de Física Atómica, Molecular y Nuclear, Universidad de
Granada, 18071
Granada,
Spain
2
Instituto de Física, Universidade Federal do Rio de
Janeiro, 21941-972
Rio de Janeiro,
Brazil
3
Department of Physics and Astronomy, University of
Aarhus, 8000
Aarhus C,
Denmark
4
CeBio y Secretaría de Investigaciones, Universidad Nacional del
Noroeste de la Prov. de Buenos Aires, UNNOBA-Conicet, Roque Saenz-Pea 456,
Junin,
Argentina
a
e-mail: arplastino@unnoba.edu.ar
Received: 6 May 2014
Received in final form: 3 August 2014
Published online: 17 November 2014
We investigate the correlations between different bipartitions of an exactly solvable one-dimensional many-body Moshinsky model consisting of Nn “nuclei” and Ne “electrons.” We study the dependence of entanglement on the inter-particle interaction strength, on the number of particles, and on the particle masses. Consistent with kinematic intuition, the entanglement between two subsystems vanishes when the subsystems have very different masses, while it attains its maximal value for subsystems of comparable mass. We show how this entanglement feature can be inferred by means of the Born-Oppenheimer Ansatz, whose validity and breakdown can be understood from a quantum information point of view.
Key words: Quantum Information
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2014
