Comment on "Formation Mechanism and Low-Temperature Instability of Exciton Rings"

Abstract

This is an extended version of the Comment that contains the criticism against an applicability of the diffusive transport model for the explanation of the ring-shaped spatial pattern formation in the exciton photoluminescence for the GaAs/AlGaAs double quantum wells [Phys. Rev. Lett. 92, 117404 (2004)]. The model has been used in other similar papers published in the PRL and the PRB afterwards.

2 pages. The text has been amended: few statements specified, one typo corrected, wrong description removed, three references removed and one added. The changes do not affect the essence of the Comment