Dissipative dynamics of interacting Bosons

Dario Poletti, Peter Barmettler, Antoine Georges +1 more

We study the dynamics of a strongly interacting bosonic quantum gas in an optical lattice potential under the effect of a dissipative environment. We show that the interplay between the dissipative process and the Hamiltonian evolution leads to an unconventional dynamical behavior of local number fluctuations. In particular, we show, both analytically and numerically, the emergence of an anomalous diffusive evolution in configuration space at short times and, at long times, an unconventional dynamics dominated by rare events. Such rare events, common in disordered and frustrated systems, are due here to strong interactions. This complex two-stage dynamics reveals information on the level structure of the strongly interacting gas.

Jeremy T. Young, Michael Foss‐Feig, Alexey Vyacheslavovich Gorshkov +1 more

Arko Roy, Kush Saha

Abstract Motivated by the recent experiments on engineering localized losses in quantum gases, we study the dynamics of interacting bosons in a two-dimensional optical lattice with local dissipation. Together with the Gutzwiller mean-field theory for density matrices and Lindblad master equation, we show how the onsite interaction between bosons affects the particle loss for various strengths of dissipation. For moderate dissipation, the trend in particle loss differs significantly near the superfluid-Mott boundary than the deep superfluid regime. While the loss is suppressed for stronger dissipation in the deep superfluid regime, revealing the typical quantum Zeno effect, the loss near the phase boundary shows non-monotonic dependence on the dissipation strength. We furthermore show that close to the phase boundary, the long-time dissipative dynamics is different from the deep superfluid regime. Thus the loss of particle due to dissipation may act as a probe to differentiate strongly-correlated superfluid regime from its weakly-correlated counterpart.

Elisheva Elbaz

Manfred J. Mark, Stuart Flannigan, Florian Meinert +3 more

We observe the dissipative dynamics of a dense, strongly interacting gas of bosonic atom pairs in an optical lattice, controlling the strength of the two-body interactions over a wide parameter regime. We study how three-body losses contribute to the lattice dynamics, addressing a number of open questions related to the effects of strong dissipation in a many-body system, including the relationship to the continuous quantum Zeno effect. We observe rapid break-up of bound pairs for weak interactions, and for stronger interactions we see doublon decay rates that are asymmetric when changing from attractive and repulsive interactions and which strongly depend on the interactions and on-site loss rates. By comparing our experimental data with a theoretical analysis of few-body dynamics, we show that these features originate from a nontrivial combination of dissipative dynamics described by a lattice model beyond a standard Bose-Hubbard Hamiltonian, and the modification of three-atom dynamics on a single site, which is generated alongside strong three-body loss. Our results open new possibilities for investigating bosonic atoms with strong three-body loss features and allow for the better understanding of the parameter regimes that are required to realize strong effective three-body interactions.

Sebastian Stumper, Michael Thoss, Junichi Okamoto