Simon Bernon
CNRS, LP2N, Université de Bordeaux

“Quantum gaz manipulation in nano-scale volumes”

Quantum gas microscopes have become an interesting platform to perform quantum simulations using ultra-cold atoms in optical lattices. They are for example used to observe long-range order such as anti-ferromagnetic correlations in far field optical lattices using density and spin resolved microscopy. Decreasing the period of such lattice offer interesting perspective to increase atom-atom interaction energies and engineer atom-light coupling. Our group tackles this goal via the hybridization of cold atoms and nano-structured surfaces.
In this presentation, I will show how such type of sub-wavelength lattice potentials can be generated by trapping atoms in close proximity (tens to hundreds of nanometers) of a nano-structured surface. At such atom to surface distance, the attractive Casimir-Polder force can be compensated by a doubly dressed state trapping method that I will discuss. Such method can additionally overcome the diffraction limit of conventional imaging that become critical for atoms trapped in sub-wavelength lattices. I will present the principle and experimental characterization of such a sub-wavelength resolution absorption imaging that achieves few tens of nanometer resolution. As an example, the method was applied to resolve, in-situ, single site wavefunction within a 1D lattice. As observed in our experiment, in such dense clouds, collective scattering effects play a significant role in the propagation of light in the medium and needs to be considered to reach quantitative measurements.
Depending on the audience interest, I can additionally present some recent work on the spectroscopy of Acetylene in sealed hollow core fibers.