Effect of matrix material on the morphology and optical properties of InP-based InAsSb nanostructures

This paper presents a study on the effect of matrix material on the morphology and optical properties of self-assembled InP-based InAsSb nanostructures. Due to the differences in surface roughness of the growth front, In0.53 Ga0.47 As matrix layer induces the formation of short quantum dashes (QDashes) and elongated quantum dots, while InP and In0.52 Al0.48 As matrix layers promote the formation of long QDashes and quantum wires, respectively. The shape anisotropy of InAsSb nanostructures on In0.53 Ga0.47 As, InP, and In0.52 Al0.48 As layers is further investigated with polarized photoluminescence measurements. The InAsSb nanostructures show a luminescence polarization degree of 8.5%, 14.3%, and 29% for In0.53 Ga0.47 As, InP, and In0.52 Al0.48 As matrixes, which corresponds well with the shape anisotropy observed with atomic force microscope. Furthermore, InAsSb/ In0.53 Ga0.47 As nanostructures also show the longest, thermally stable emission wavelength, which serves as a promising material system for fabricating midinfrared emitters.