Abstract

Partly non-degenerate four-wave mixing is able to detect coherent coupling between excitonic resonances like e.g. light-hole and heavy-hole excitons or between an exciton and its continuum states.¹ We apply an extension of this method, which we call selective coherent spectroscopy (SCS), to symmetrically strained (GaIn)As/Ga(PAs) multiple quantum-wells. The samples are excited simultaneously by a picosecond pulse with wavevector k₁ and a 100 fs pulse with wavevector k₂. The central wavelength of the picosecond pulse is scanned over the entire spectrum of the 100 fs pulse and the four-wave mixing signal in the direction 2k₂ – k₁ is detected at a fixed energy. This scan provides an SCS spectrum.

© 1999 Optical Society of America