Pouring Excitons into a Two-Dimensional Bucket: Equilibration of Indirect Excitons in an In-Plane Harmonic Potential

TL;DR

This paper demonstrates trapping and thermalization of long-lifetime excitons in a harmonic potential, highlighting the dominant role of exciton interactions and advancing toward exciton Bose-Einstein condensation.

Contribution

It introduces a method to trap excitons in an in-plane harmonic potential and shows their thermalization, emphasizing the importance of exciton interactions unlike atomic gases.

Findings

Excitons can be trapped in a harmonic potential with high mobility.

Excitons thermalize to a well-defined equilibrium distribution.

Repulsive interactions dominate exciton behavior in the trap.

Abstract

We have trapped a gas of long-lifetime, high-mobility excitons in an in-plane harmonic potential. Trapping is an important step toward the goal of a controlled Bose-Einstein condensate of excitons. We show that the repulsive interaction between the excitons plays a dominant role in the behavior of the excitons, in contrast to the weak interactions in atomic gases. We show that under proper conditions the excitons thermalize in the trap to a well-defined equilibrium spatial distribution.