Stefan S. Natu

Local versus global equilibration near the bosonic Mott-insulator-superfluid transition.

We study the time scales for adiabaticity of trapped cold bosons subject to a time-varying lattice potential using a dynamic Gutzwiller mean-field theory. We explain apparently contradictory experimental observations by demonstrating a clear separation of time scales for local dynamics (~ ms) and global mass redistribution (~1 s). We provide a simple explanation for the short and fast time scales, finding that while density or energy transport is dominated by low energy phonons, particle-hole excitations set the adiabaticity time for fast ramps. We show how mass transport shuts off within Mott-insulator domains, leading to a chemical potential gradient that fails to equilibrate on experimental time scales.

Dynamics of correlations in a dilute Bose gas following an interaction quench

We calculate the dynamics of the one and two body correlation functions in a homogeneous Bose gas at zero temperature following a sudden change in the interaction strength, with and without an underlying lattice. We focus on conceptually simple examples that highlight the features arising separately from interactions and band structure. In the continuum, we show that the Bogoliubov spectrum leads to a diffusive evolution of density correlations for short times, and ballistic at long times. In the lattice we find that the correlation functions develop additional oscillations. Moreover, the lattice dispersion induces an additional velocity scale, and some features instead propagate with that velocity. Finally, we discuss the time-evolution of the contact following a quench. Our predictions, which can be readily tested in experiments, serve as a benchmark for considering the dynamics of more complicated systems.

Striped Ferronematic ground states in a spin-orbit coupled spin-1 Bose gas

We theoretically establish the mean-field phase diagram of a homogeneous spin-

Evolution of condensate fraction during rapid lattice ramps

1

Landau damping in a collisionless dipolar Bose gas

, spin-orbit coupled Bose gas as a function of the spin-dependent interaction parameter, the Raman coupling strength and the quadratic Zeeman shift. We find that the interplay between spin-orbit coupling and spin-dependent interactions leads to the occurrence of ferromagnetic or ferronematic phases which also break translational symmetry. For weak Raman coupling, increasing attractive spin-dependent interactions (as in

Domain-wall dynamics in a two-component Bose-Mott insulator

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Static and dynamic properties of interacting spin-1 bosons in an optical lattice

Rb or

Dynamics of correlations in a quasi-two-dimensional dipolar Bose gas following a quantum quench

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Real-space mean-field theory of a spin-1 Bose gas in synthetic dimensions

Li) induces a transition from a uniform to a stripe XY ferromagnet (with no nematic order). For repulsive spin-dependent interactions however (as in

Bosons with long-range interactions on two-leg ladders in artificial magnetic fields

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