We study excitonic states in the presence of applied electric field in 8-nm GaAs coupled quantum wells ~QW’s! separated by a 4-nm Al0.33Ga0.67As barrier and in 6-nm In0.1Ga0.9As coupled QW’s separated by a 4-nm GaAs barrier in which effects attributed to macroscopically ordered excitonic states have been recently reported. We discuss the differences in the nature of the states and in the origin...

in InGaN/GaN multiple quantum wells L. Dong, J. V. Mantese, V. Avrutin, € U. € Ozg€ ur, H. Morkoç, and S. P. Alpay Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA United Technology Research Center, East Hartford, Connecticut 06108, USA Department of Electrical and Computer Engineering, Virginia Commonwealth University, Richmond, Virginia 23284-3072, USA Departme...