Commensurate to incommensurate transitions and frustration in multi-component Rydberg gases

Emanuele Levi, Jiří Minář, Juan P. Garrahan, Igor Lesanovsky

Published Mar 11, 2015• 0 citations

Abstract

We study the static behavior of a gas of atoms held in a one-dimensional lattice where two distinct electronically high-lying Rydberg states are simultaneously excited by laser light. We focus on a situation where interactions of van-der-Waals type take place only among atoms that are in the same Rydberg state. We analytically investigate at first the so-called classical limit of vanishing laser driving strength. We show that the system exhibits a surprisingly complex ground state structure with a sequence of commensurate to incommensurate transitions. The incommensurability between the species leads to mutual frustration, a feature which pertains also in the quantum regime. We perform an analytical and numerical investigation of these features and present an approximative description of the system in terms of a Rokhsar-Kivelson Hamiltonian which permits the analytical understanding of the frustration effects even beyond the classical limit.

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