Researchers have shown that an unusual class of quantum states known as “fractional Fermi seas” can be deliberately created, according to a new study published in Physical Review Letters. The work was carried out by the Nägerl group together with theoretical physicist Alvise Bastianello of CNRS and Université Paris-Dauphine.
The study demonstrates how a new critical phase of matter can emerge when quantum particles are pushed far from their normal equilibrium conditions. Using ultracold cesium atoms confined to one dimension, the researchers repeatedly altered how strongly the particles interacted with one another. The resulting state goes beyond the behavior predicted by the well-known Tomonaga-Luttinger liquid theory, a cornerstone for understanding one-dimensional quantum systems.
This publication provides the theoretical framework for recent experimental research conducted in the group of Hans-Christoph Nägerl at the Department of Experimental Physics.
