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Interacting ultracold atomic kicked rotors: loss of dynamical localization.

ABSTRACT: We study the fate of dynamical localization of two quantum kicked rotors with contact interaction, which relates to experimental realizations of the rotors with ultra-cold atomic gases. A single kicked rotor is known to exhibit dynamical localization, which takes place in momentum space. The contact interaction affects the evolution of the relative momentum k of a pair of interacting rotors in a non-analytic way. Consequently the evolution operator U is exciting large relative momenta with amplitudes which decay only as a power law 1/k⁴. This is in contrast to the center-of-mass momentum K for which the amplitudes excited by U decay superexponentially fast with K. Therefore dynamical localization is preserved for the center-of-mass momentum, but destroyed for the relative momentum for any nonzero strength of interaction.

SUBMITTER: Qin P

PROVIDER: S-EPMC5259732 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Interacting ultracold atomic kicked rotors: loss of dynamical localization.

Qin Pinquan P Andreanov Alexei A Park Hee Chul HC Flach Sergej S

Scientific reports 20170124

We study the fate of dynamical localization of two quantum kicked rotors with contact interaction, which relates to experimental realizations of the rotors with ultra-cold atomic gases. A single kicked rotor is known to exhibit dynamical localization, which takes place in momentum space. The contact interaction affects the evolution of the relative momentum k of a pair of interacting rotors in a non-analytic way. Consequently the evolution operator U is exciting large relative momenta with ampli ...[more]

PMID: 28117347

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