Nuclear Physics Seminar

"Observation of emergent hydrodynamic behavior in a mesoscopic 2D Fermi gas"

Presented by Giuliano Giacalone, ITP - Universität Heidelberg

Tuesday, August 23, 2022, 11:00 am — Videoconference / Virtual Event (see link below)

Abstract: Emergent hydrodynamic behavior is observed in many-body systems across vastly different temperature scales. Motivated by the recent observation of collective particle emission in high-energy proton-proton collisions, where particle numbers are small and a fluid description is a priori inapplicable, we perform an experimental investigation of hydrodynamic behavior in two-dimensional Fermi gases with tunable particle number. To assess the emergence of a collective expansion, we study the inversion of the shape of gases prepared in elliptical traps. Shape inversion is a salient signature of an effective pressure-gradient force, ascribable to hydrodynamics. To overcome the finiteness of the number of particles, experiments are repeated a statistically significant number of times, and statistical measures of the cloud shapes are devised. This is, hence, analogous to the analysis of collective behavior in the case of high-energy proton-proton experiments.

Clouds of few fermions, from 6 atoms up to 14 atoms, are found to exhibit strong collectivity. We conclusively determine that such observations emerge from atom-atom interactions occurring during the expansion of the system,
and can not be ascribed to underlying effects of quantum statistics. Interpreting these results as an emergent pressure-gradient force, we show that ideal hydrodynamic predictions closely match the experimental observations. We discuss the broad implications of this finding.

Hosted by: Jiangyong Jia

Join Videoconference More Information

18004  |  INT/EXT  |  Events Calendar


Not all computers/devices will add this event to your calendar automatically.

A calendar event file named "calendar.ics" will be placed in your downloads location. Depending on how your device/computer is configured, you may have to locate this file and double click on it to add the event to your calendar.

Event dates, times, and locations are subject to change. Event details will not be updated automatically once you add this event to your own calendar. Check the Lab's Events Calendar to ensure that you have the latest event information.