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Quenched Dynamics of the Momentum Distribution of the Unitary Bose Gas

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Abstract

We study the quenched dynamics of the momentum distribution of a unitary Bose gas under isotropic harmonic confinement within a time-dependent density functional approach based on our recently calculated Monte Carlo bulk equation of state. In our calculations the inter-atomic s-wave scattering length of the trapped bosons is suddenly increased to a very large value and the real-time evolution of the system is studied. Prompted by the very recent experimental data of 85Rb atoms at unitarity (Makotyn et al. in Nat Phys 10:116, 2014) we focus on the momentum distribution as a function of time. Our results suggest that at low momenta, a quasi-stationary momentum distribution is reached after a long transient, contrary to what found experimentally for large momenta which equilibrate on a time scale shorter than the one for three body losses.

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Authors and Affiliations

  1. Dipartimento di Fisica e Astronomia “Galileo Galilei” and CNISM, Università di Padova, via Marzolo 8, 35122, Padova, Italy

    Francesco Ancilotto, Maurizio Rossi, Luca Salasnich & Flavio Toigo

  2. CNR-IOM Democritos, via Bonomea, 265, 34136, Trieste, Italy

    Francesco Ancilotto & Flavio Toigo

  3. CNR-INO, via Nello Carrara, 1, 50019, Sesto Fiorentino, Italy

    Luca Salasnich

Authors
  1. Francesco Ancilotto
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  2. Maurizio Rossi
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  3. Luca Salasnich
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  4. Flavio Toigo
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Correspondence to Maurizio Rossi.

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Ancilotto, F., Rossi, M., Salasnich, L. et al. Quenched Dynamics of the Momentum Distribution of the Unitary Bose Gas. Few-Body Syst 56, 801–807 (2015). https://doi.org/10.1007/s00601-015-0971-2

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  • DOI: https://doi.org/10.1007/s00601-015-0971-2

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