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Ultrafast electron cooling in an expanding ultracold plasma.

ABSTRACT: Plasma dynamics critically depends on density and temperature, thus well-controlled experimental realizations are essential benchmarks for theoretical models. The formation of an ultracold plasma can be triggered by ionizing a tunable number of atoms in a micrometer-sized volume of a ⁸⁷Rb Bose-Einstein condensate (BEC) by a single femtosecond laser pulse. The large density combined with the low temperature of the BEC give rise to an initially strongly coupled plasma in a so far unexplored regime bridging ultracold neutral plasma and ionized nanoclusters. Here, we report on ultrafast cooling of electrons, trapped on orbital trajectories in the long-range Coulomb potential of the dense ionic core, with a cooling rate of 400 K?ps^-1. Furthermore, our experimental setup grants direct access to the electron temperature that relaxes from 5250 K to below 10 K in less than 500 ns.

SUBMITTER: Kroker T

PROVIDER: S-EPMC7838291 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Ultrafast electron cooling in an expanding ultracold plasma.

Kroker Tobias T Großmann Mario M Sengstock Klaus K Drescher Markus M Wessels-Staarmann Philipp P Simonet Juliette J

Nature communications 20210126 1

Plasma dynamics critically depends on density and temperature, thus well-controlled experimental realizations are essential benchmarks for theoretical models. The formation of an ultracold plasma can be triggered by ionizing a tunable number of atoms in a micrometer-sized volume of a <sup>87</sup>Rb Bose-Einstein condensate (BEC) by a single femtosecond laser pulse. The large density combined with the low temperature of the BEC give rise to an initially strongly coupled plasma in a so far unexpl ...[more]

PMID: 33500420

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