Exciton Transport in Electrostatic Lattices

lattice_small.001 lattice_small.002
We study transport of indirect excitons in GaAs/AlGaAs coupled quantum wells in linear lattices created by laterally modulated gate voltage. The localization-delocalization transition for transport across the lattice was observed with reducing lattice amplitude or increasing exciton density. The exciton interaction energy at the transition is close to the lattice amplitude. These results are consistent with the model, which attributes the localization-delocalization transition to the interaction-induced percolation of the exciton gas through the external potential.

M. Remeika, J. C. Graves, A. T. Hammack, A. D. Meyertholen, M. M. Fogler, L. V. Butov, M. Hanson, and A. C. Gossard, Localization-Delocalization Transition of Indirect Excitons in Lateral Electrostatic Lattices, arXiv:0901.1349v1 (2009); Phys. Rev. Lett. 102, 186803 (2009).