physica status solidi (b)
Superradiant Coupling of Excitons in (In,Ga)As Multiple Quantum Wells
M. H�bner, J. Kühl, Bernd Grote, T. Stroucken, S. Haas, A. Knorr, S. W. Koch, G. Khitrova, H. M. Gibbs
Abstract
The third order nonlinear optical response at the heavy-hole (hh) exciton resonance in a wedge-shaped multiple quantum well structure close to the Bragg resonance is investigated using time-integrated and spectrally resolved degenerate four-wave mixing. Effective interwell exciton–exciton interaction due to photon exchange is demonstrated by studying the signals in backward direction for different widths of the barriers.