The effects of large deformation were studied by preparing thin (20-30 μm) membranes with quantum-well layers on top. A small gas pressure of a few bar deforms the membrane substantially and changes the optical spectra of the quantum wells. We present the results of the photoluminescence and absorption from GaAs/AlGaAs and from InGaAs/GaAs quantum wells subjected to tensile and to compressive biaxial strain. The light-hole lines shift more than two times faster than the heavy-hole lines so that they cross under tensile strain.
The interband absorption of strained InGaAs/GaAs multiple quantum well was studied at room temperature for pressures up to 5.5 GPa. Three absorption lines were attributed to the excitonic transitions hh1-e1, lh1-e1 and hh2-e2. They were visible until pressure of about 5 GPa which is above the Γ-X crossover for this system. Pressure coefficients of the observed lines were compared with the literature data. The origin of broadening of the lines above Γ-X crossover is discussed.
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.