Abstract

The ability to control the internal and external degrees of freedom of individual or ensembles of atoms has been breathtaking in the last three decades. Nowadays, laser cooled atoms and degenerate quantum gases are almost routinely produced in many laboratories all over the world. This rapid development has produced a tremendous interest in utilizing atomic systems to explore their quantum properties in technological applications such as quantum information processing, quantum sensing, and quantum computation. I will present experiments that demonstrate a few of those quantum technologies: First, a quantum metrology application of optically trapped and laser-cooled rubidium 87 atoms is presented. Where, we have been able to produce a spin squeezed state of an ensemble of one million atoms, which shows a twofold sensitivity enhancement compared to the standard quantum limit. Second, two-dimensional Fermi gases of ultracold potassium 40 atoms serve as a quantum simulator for many-body physics in two dimensions. As an example, the physics of a single fermionic spin impurity in a fermionic bath is studied and the defining properties of the emergent quasi-particle – the Fermi polaron – are determined. Further, the limits of spin diffusion are explored for a strongly interacting two-dimensional Fermi gas and we observe the lowest spin diffusivity ever measured. In the end, will outline a possible quantum information platform based on single neutral atom strongly coupled to the electromagnetic field mode of nano-photonic structures.