Synthetic Lorentz force in an expanding cold atomic gas

Abstract

We implement a synthetic Lorentz force in a cold atomic gas released from a magneto-optical trap. The signature of this is an angular deflection of a rotationally asymmetrical cloud. The effect is a consequence of thermal expansion of the cold atomic cloud under the influence of the applied synthetic Lorentz force. The synthetic Lorentz force is based on radiation pressure and the Doppler effect, making it straightforward to implement. The introduction of synthetic magnetism into our system, together with the fact that it is readily described by the Fokker-Planck equation, makes it an excellent candidate to emulate numerous complex classical systems.

Two-temperature Brownian dynamics of a particle in a confining potential

“…Breaking the two symmetries in this case, we wonder to what extent this thermal rotation can be observed. Rotation of atomic clouds have been previously reported in the context of a beam-misaligned vortex trap [19,20] and more recently using synthetic Lorentz forces [21][22][23]. As opposed to those previous studies where the rotation is due to a net mean radiation pressure forces, our proposal is based on a stochastic force with zero mean value.…”

Non-equilibrium long-range phase transition in cold atoms : theory and experiment

“…Breaking the two symmetries in this case, we wonder to what extent this thermal rotation can be observed. Rotation of atomic clouds have been previously reported in the context of a beam-misaligned vortex trap [59,177] and more recently using synthetic Lorentz forces [178,179,180]. As opposed to those previous studies where the rotation is due to a net mean radiation pressure force, our proposal is based on a stochastic force with zero mean value.…”