Open Positions



We are always interested in prospective PhD students as well as postdocs. Also, students are encouraged to apply for semester/bachelor/master projects at any time. For information or application, please contact Tilman Esslinger and/or Tobias Donner.



Postdoc Opening


Engineering Strongly-Correlated Magnetic Systems with Long-Range Interactions

In our experiment, we couple a Bose-Einstein condensate (BEC) to an ultrahigh- finesse optical resonator to study cavity QED in many-body quantum systems. In the dispersive regime, we engineer long-range interactions by photon scattering from external drives. At a critical driving strength, the system undergoes a Dicke phase transition to a superradiant crystal. The inherent loss from the cavity mirrors provides non-destructive, real-time access to the dynamics and, at the same time, introduces dissipative coupling channels.

In recent projects, we have selectively addressed the internal atomic spin and investigated novel phases and dynamics arising from the interplay between coherent and dissipative couplings. We discovered chiral instabilities and limit- cycles in a spinor BEC coupled to two different atomic spatial configurations by exploiting a dissipative coupling between the light quadrature mediating these modes [1]. Moreover, we observed an emergent dissipation- stabilized dark phase by tuning the competition between coherent and dissipative processes in a Raman-coupled BEC. We uncovered the microscopic mechanism by probing the properties of the underlying light-matter excitations [2]. In a very recent experiment, we engineered dynamical tunneling in a two-dimensional synthetic lattice momentum space. The emerging currents are mediated by a state-dependent photon field and can be locally resolved via the leaking cavity field [3].

Starting point for future projects is to investigate emergent magnetic phenomena in strongly-correlated systems featuring cavity-assisted long-range interactions. This regime can be accessed by enhancing on- site interactions in a three-dimensional optical lattice [4]. Besides the prospect of discovering unconventional magnetic phases, such systems hold the potential to realize dynamical gauge fields and advance the simulation of lattice gauge theories. A strong background in experimental quantum gas physics and theoretical many-body physics is desirable, and you should enjoy working in a small team with 2-3 PhD students. Starting time of the PostDoc is at your earliest convenience.



References:
[1] Dogra, N., Landini, M., Kroeger, K., Hruby, L., Donner, T., Esslinger, T. (2019). Science, 366(6472), 1496-1499.
[2] Ferri, F., Rosa-Medina, R., Finger, F., Dogra, N., Soriente, M., Zilberberg, O., Donner, T., Esslinger, T. (2021). arXiv:2104.12782.
[3] Rosa-Medina, R., Ferri, F., Finger, F., Dogra, N., Kroeger, K., Lin, R., Chitra, R., Donner, T., Esslinger, T. (2021). In preparation
[4] Landig, R., Hruby, L., Dogra, N., Landini, M., Mottl, R., Donner, T., & Esslinger, T. (2016). Nature, 532(7600), 476-479.

Please contact:
Prof. Tilman Esslinger
esslinger@phys.ethz.ch
ETH Zurich, Otto-Stern-Weg 1, CH-8093 Zürich

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