Ultracold and ultrafast: Probing quantum gases with ion microscopy and electron spectroscopy*

Ultrashort laser pulses offer new opportunities for probing and manipulating ultracold quantum gases. The strong light field of such a laser pulse can locally ionize few or many atoms in a Bose-Einstein condensate, enabling the creation of hybrid quantum systems combining ultracold atoms and ions. The large bandwidth of the laser pulse additionally allows ultrafast excitation of interacting Rydberg atoms below the blockade radius within femtoseconds.

Here we present a novel detection unit for charged particle analysis of ultracold atoms consisting of an ion microscope and a velocity-map-imaging electron spectrometer tailored to resolve the dynamics of these systems. The ion microscope tracks the position of ions with a high spatial resolution, while the velocity-map-imaging spectrometer measures the momentum of the electrons over several orders of magnitude.

Both devices can be operated simultaneously, allowing coincidence measurements due to the high detection efficiencies. A time-resolved extraction and detection on single digit nanosecond timescales enables observing the emergence of correlations and many-body phenomena in interacting quantum systems of charged particles.