Effect of strain on the electronic structure of indium - gallium-arsenide--an angle-resolved photoemission study

ngle-resolved photoemission spectroscopy has been used to study the effect of strain on the electronic structure of InGaAs substitutional pseudobinary alloys. Two types of strain were considered. One is the bond length disorder due to the size-mismatch in the pseudobinary alloys. The other is the pseudomorphic strain due to lattice-mismatch at the interface in the heterostructures. Three aspects of the effect of strain on the electronic structure were examined: (1) alloy bowing effect in InGaAs alloys, (2) K-resolved deformation potential of InGaAs alloys, and (3) natural valence band offset in InGaAs alloys.;K-resolved alloy bowing data in InGaAs supports that the bond-length disorder can cause extra bowing in the valence band structure. The two upper valence bands are shifted upward in energy, while the lower is shifted downward in energy. We also found that the implementation of bond-length disorder in the molecular coherent potential approximation has to be modified.;A series of angle-resolved photoemission spectra taken from the GaAs(001) in the strained layer heterostructures enable us to determine the strain-induced energy shift of electron states. We found that different bands respond differently to the strain perturbation. Experimental evidences also indicates that the role of In alloying in InGaAs alloys is to reduce strain-induced effects.;The natural valence band offset (NVBO) at the InGaAs/GaAs interface was determined using the alloy approach. We found that the NVBO at the InGaAs/GaAs interfaces is (0.20x...