KRb Mixtures

We are interested in the out-of-equilibrium dynamics and quantum simulation of one-dimensional (1D) systems. As our model system we use 1D superfluids realized by cooling 87Rb atoms to degeneracy in the elongated magnetic confinement of an atom chip. Through additional rf-dressing we are able to create a parallel pair of these systems with a tunable tunnel coupling. A superposed optical dipole potential further lets us augment the confinement along the 1D axis. We probe the system mainly via matter-wave interference and correlation analysis giving us unprecedented insight into the underlying many-body physic. All this provides us with a tunable and well-controlled platform to investigate relaxation dynamics, the effects of periodic driving or the equilibrium correlations of non-trivial field theories.

With our setup we also have the possibility to produce mixtures of potassium and rubidium which might hold interesting possibilities for future projects.


  • Relaxation dynamics after changing the tunnel-coupling strength:

    By changing the tunnel coupling strength, we are able to change the interactions between the collective excitations in our system. This lets us experimentally investigate the question how correlations evolve after such a change. In particular, we are looking at the build-up/decay of non-Gaussian correlations during the evolution.

  • Periodic driving:

    We are planning to investigate a variety of physical phenomena by periodically changing the confining potential. Modulating the confinement along the elongated direction, we want to excite a single collective excitation and observe its subsequent decay. Periodically changing the transverse confinement should enable us to change the sign of the effective the tunnel-coupling, thus allowing quenches between tunnel-couplings with opposite signs.

  • Thermodynamic protocols:

    A digital micro-mirror device used to spatially modulate the dipole trap light will give us an arbitrary control over the potential landscapes. Among other projects, this will enable us to study small systems coupled to big reservoirs and to implement thermal machines.

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Local emergence of thermal correlations in an isolated quantum many-body system, Nature Physics (2013) 37-10xexternal