Luogo: Polo Ferrari 1 via Sommarive 5 Povo - Room A204
prof . Antoine Browaeys
Laboratoire Charles Fabry, Institut d’Optique, CNRS, Palaiseau, France
This talk will present our effort to control and use the dipole-dipole interactions between cold Rydberg atoms in order to implement spin Hamiltonians useful for quantum simulation of condensed matter situations. We trap individual atoms in arrays of optical tweezers separated by few micrometers and excite them to Rydberg states. We create almost arbitrary geometries of the arrays with unit filling in two and three dimensions up to about 70 atoms.
We have demonstrated the coherent energy exchange in chains of Rydberg atoms resulting from their resonant dipole-dipole interaction and its control by addressable lasers. This interaction realizes the XY spin model and leads to the hopping a spin excitation from a site to another. We use this interaction to study elementary excitations in a dimerized spin chain featuring topological properties, thus implementing the Su-Schrieffer-Heeger model. We have observed the edge states in the topological condition. We explored the regime beyond the linear response by adding several excitations, which act as hard-core bosons. By studying the properties of the system at half filling, we find out that it realizes a symmetry protected topological phase, the only possible topological order in one dimension. Recently, we extended the use of this resonant interaction to implement a spin-orbit coupling, leading to an emergent gauge field.
This control of an ensemble of interacting Rydberg atoms demonstrates an interesting platform for quantum simulation using neutral atoms, complementary to the other platforms based on ions, magnetic atoms or dipolar molecules.
dr. Iacopo Carusotto