Eur. Phys. J. A (2010) 43: 229-240
https://doi.org/10.1140/epja/i2010-10910-6

Regular Article - Theoretical Physics

On the modification of the Efimov spectrum in a finite cubic box

Helmholtz-Institut für Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics, Universität Bonn, 53115, Bonn, Germany

^* e-mail: kreuzer@hiskp.uni-bonn.de

Received: 13 October 2009
Revised: 14 December 2009
Accepted: 15 December 2009
Published online: 16 January 2010

Abstract

Three particles with large scattering length display a universal spectrum of three-body bound states called “Efimov trimers”. We calculate the modification of the Efimov trimers of three identical bosons in a finite cubic box and compute the dependence of their energies on the box size using effective field theory. Previous calculations for positive scattering length that were perturbative in the finite-volume energy shift are extended to arbitrarily large shifts and negative scattering lengths. The renormalization of the effective field theory in the finite volume is explicitly verified. We investigate the effects of partial-wave mixing and study the behavior of shallow trimers near the dimer energy. Moreover, we provide numerical evidence for universal scaling of the finite-volume corrections.