Year: 2012
Type: article
Abstract: We propose that negative absolute temperatures in ultracold atomic clouds in optical lattices can be used to simulate quantum systems in new regions of phase diagrams. First we discuss how the attractive SU(3) Hubbard model in three dimensions can be realized using repulsively interacting ${}^{173}$Yb atoms, then we consider how an antiferromagnetic $S=1$ spin chain could be simulated using spinor ${}^{87}$Rb or ${}^{23}$Na atoms. The general idea to achieve negative absolute temperatures is to reverse the sign of the external harmonic potential. Energy conservation in a deep optical lattice imposes a constraint on the dynamics of the cloud, which can relax toward a $T<0$ state. As the process is strongly nonadiabatic, we estimate the change of the entropy.
Source: Physical Review A
Author: Ákos Rapp
Institutions: Leibniz University Hannover, University of Cologne
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2093759744