The well-width dependence of in-plane optical anisotropy (IPOA) in (001) GaAs/AlxGa1−xAs quantum wells induced by in-plane uniaxial strain and interface asymmetry has been studied comprehensively. Theoretical calculations show that the IPOA induced by in-plane uniaxial strain and interface asymmetry exhibits much different well-width dependence. The strain-induced IPOA is inversely proportional to the energy spacing between heavy- and light-hole subbands, so it increases with the well width. However, the interface-related IPOA is mainly determined by the probability that the heavy- and light-holes appear at the interfaces, so it decreases with the well width. Reflectance difference spectroscopy has been carried out to measure the IPOA of (001) GaAs/AlxGa1−xAs quantum wells with different well widths. Strain- and interface-induced IPOA have been distinguished by using a stress apparatus, and good agreement with the theoretical prediction is obtained. The anisotropic interface potential parameters are also determined. In addition, the energy shift between the interface- and strain-induced 1H1E reflectance difference (RD) structures, and the deviation of the 1L1E RD signal away from the prediction of the calculation model have been discussed.

Well-width dependence of in-plane optical anisotropy in (001) GaAs/AlGaAs quantum wells induced by in-plane uniaxial strain and interface asymmetry In-plane optical anisotropy of symmetric and asymmetric (001) GaAs/Al(Ga)As superlattices and quantum wells J. Appl. Phys. 90, 1266 (2001); 10.1063/1.1383018In-plane birefringence of asymmetric (001) quantum wells Appl.It is well known that asymmetry in the ͑001͒ direction can induce in-plane optical anisotropy ͑IPOA͒ in ͑001͒ quantum wells ͑QWs͒. In this letter, asymmetry is introduced in ͑001͒ GaAs/ AlGaAs QWs by inserting 1 ML ͑monolayer͒ of InAs or AlAs at interfaces. Strong IPOA, which is comparable to that in the InGaAs/ InP QWs with no common atom, is observed in the asymmetric GaAs/ AlGaAs QW by reflectance difference spectroscopy.