Study of excitonic transitions in δ-doped GaAs/AlAs quantum wells

Terahertz-optical mixing in undoped and doped GaAs quantum wells: From excitonic to electronic intersubband transitions

S. G. Carter,1,* V. Ciulin,1,† M. Hanson,2 A. S. Huntington,2,‡ C. S. Wang,3 A. C. Gossard,2,3 L. A. Coldren,2,3 and M. S. Sherwin1 1Physics Department and iQUEST, University of California, Santa Barbara, California 93106, USA 2Materials Department, University of California, Santa Barbara, California 93106, USA 3Electrical and Computer Engineering Department, University of California, Santa Bar...

Coherent excitonic effects in quantum wells

Excitonic Radiative Dynamics in Multiple Quantum Wells

The fundamental intrinsic radiative process associated with excitons in semiconductor multiple quantum wells is discussed within the context of exciton polaritons. Multiple quantum wells in which each well is randomly displaced from its ideal periodic position are discussed in order to investigate the effect of disorder on excitonic radiative widths. The coherent transpori of excitons in multip...

Excitonic binding in coupled quantum wells

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...

Subpicosecond excitonic optical nonlinearities in quantum wells

2014 Excitonic resonances in semiconductors are very sensitive to applied optical fields. We present here a comparison between the effects of resonant and non resonant optical excitation, creating respectively real or virtual excitons. A blue shift of the exciton line and a reduction of the oscillator strength are simultaneously observed in multiple-quantum-well-structures for the two following...