QUANTUM CONFINED STARK-EFFECT IN INGAAS-INP AND INGAAS-INGAASP MULTI-QUANTUM-WELL STRUCTURES

Differential electrotransmission measurements on InGaAs/InP and InGaAs/InGaAsP multi quantum well structures (MQW) with well widths 8,10 and 20 nm with InGaAsP barriers of Eg(77 K) = 1.2 eV are presented. The differential electrotransmission spectra were fitted with a lorentzian lineshape model for the excitonic transition. A Stark shift of up to 18 meV was observed for the 8 nm InGaAs/InGaAsP quantum well structure. The results were compared to a calculation of the Stark effect including the field dependent exciton binding energy. We find good agreement between experiment and theory. The well width dependence of the oscillator strength shows a maximum for Lz = 11 nm when changing the field from 1 · 104V/cm to 1 · 105V/cm. © 1990.