Photocurrent spectroscopy of InxGa1minus;xAs/GaAs multiple quantum wells

摘要

Photocurrent spectra of InxGa1minus;xAs/GaAs multiple quantum well structures grown by molecular beam epitaxy are studied in the presence of electric fields perpendicular to the heterointerface. Several Dgr;n=0 allowed and Dgr;nne;0 forbidden excitonic transitions are observed. Both negative and positive shifts of exciton transitions are found. Good agreement is found between the photocurrent observations and calculations using a multiband effectivehyphen;mass approach, taking into account the strainhyphen;induced splitting.