Coherence Length of Cold Exciton Gases in Coupled Quantum Wells

Sen Yang, A. T. Hammack, M. M. Fogler, L. V. Butov, A. C. Gossard
2006 Physical Review Letters  
A Mach-Zehnder interferometer with spatial and spectral resolution was used to probe spontaneous coherence in cold exciton gases, which are implemented experimentally in the ring of indirect excitons in coupled quantum wells. A strong enhancement of the exciton coherence length is observed at temperatures below a few Kelvin. The increase of the coherence length is correlated with the macroscopic spatial ordering of excitons.
doi:10.1103/physrevlett.97.187402 pmid:17155574 fatcat:tzzbrrw3cjgg5dxra4n5gkfm3i