Properties of electrons and excitons in graded quantum wells of Ga_1-xAl_xAs in an electric field

Abstract

Using the method of series expansion, sub-bands of electrons and holes, electronhole overlap functions and binding energies of excitons are calculated for the graded quantum well of Ga,_xAI,As with a Gao66A1034As barrier in the electric field F between 0 and *9 (lo4 V cm-I). The width of the well is 200 A, and the electric field is perpendicular to the material layers. The calculations reveal that the behaviour of electrons and excitons in this well is very different from that in square quantum wells and is useful for some device applications.