[Seminar] 'Ultrafast Rydberg experiments with ultracold atoms' by Dr Sylvain de Léséleuc

Title: Ultrafast Rydberg experiments with ultracold atoms

Presenter: Sylvain de Léséleuc Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki (Japan)

Abstract: Rydberg atoms, with their giant electronic orbitals, exhibit dipole-dipole interaction reaching the GHz range at a distance of a micron (C3 ~ GHz.μm3), making them a prominent contender for realizing ultrafast quantum operations. However, such strong interactions have never been harnessed so far because of the stringent requirements on the fluctuation of the atom positions and the necessary excitation strength. Here, we introduce novel techniques to enter and explore this ultrafast Rydberg regime [1,2].

I will first introduce the Rydberg timescale to position the various fundamental limits and opportunities set by atomic physics properties, as well as the technical challenges in reaching them with today’s experimental tools. We will then look at how we excite Rydberg atoms as fast as physically possible (~10 picoseconds) by pulsed lasers, non-linear optics and spectral optimization. With the atoms now in the Rydberg states, we will revisit how fast they can interact with each other through long-range dipole-dipole interaction and demonstrate coherent dynamics in the nanosecond timescale. Finally, we will consider how the internal electronic Rydberg dynamics driven by interaction couples coherently to the external motional degrees of freedom (position, momentum). I will show signatures of this effective “spin-motion” coupling on experiments with atoms trapped in optical tweezers and optical lattices, and opportunities offered by quantum control of the motional states on both platform [3].

Sponsored by SPIE and Optica Student Chapters