Spatial Coherence of a Polariton Condensate

TL;DR

This study investigates the spatial coherence of a polariton condensate using Young's double-slit experiment, confirming macroscopic coherence buildup and near-Heisenberg limit uncertainty, which could enable advanced matter-wave phenomena in solid-state systems.

Contribution

It provides experimental evidence of the spatial coherence properties and minimum uncertainty wave packets of polariton condensates, advancing understanding of their quantum behavior.

Findings

Coherence length increases with pump rate, indicating spontaneous coherence buildup.

The condensate's uncertainty product approaches the Heisenberg limit.

Potential for observing Josephson oscillations, superfluidity, and solitons in solid-state condensates.

Abstract

We perform Young's double-slit experiment to study the spatial coherence properties of a two-dimensional dynamic condensate of semiconductor microcavity polaritons. The coherence length of the system is measured as a function of the pump rate, which confirms a spontaneous buildup of macroscopic coherence in the condensed phase. An independent measurement reveals that the position and momentum uncertainty product of the condensate is close to the Heisenberg limit. An experimental realization of such a minimum uncertainty wave packet of the polariton condensate opens a door to coherent matter-wave phenomena such as Josephson oscillation, superfluidity, and solitons in solid state condensate systems.