Polarization dependence of the electroabsorption in lowhyphen;temperature grown GaAs for above bandhyphen;gap energies

摘要

We have measured the electroabsorption in lowhyphen;temperature grown GaAs by performing roomhyphen;temperature transmission experiments in the spectral range from 1.3 to 1.9 eV for different electric fields induced by a voltage applied to a metalhyphen;semiconductorhyphen;metal structure. The devices were separated from the substrate by using an epitaxial liftoff technique. Therefore, we have been able to observe the electrohyphen;optic effect at the fundamental band gap as well as at the splithyphen;off band edge. The absorption is clearly polarization dependent at the fundamental band gap but only weakly at the splithyphen;off band gap, in agreement with the theory of the Franzndash;Keldysh effect. copy;1996 American Institute of Physics.