Structural and optical properties of InAs quantum dot chains grown on nanoimprint lithography structured GaAs with different pattern orientations

Abstract

We use large-scale UV nanoimprint lithography prepatterned GaAs substrates for site-controlled growth of InAs quantum dot chains by molecular beam epitaxy. We demonstrate simultaneous fabrication of quantum dot chains with high optical quality along four different crystal orientations, [011], [011¯], [010], and [001]. We show that the [011¯], [010], and [001]-oriented quantum dot chains not only have similar morphology but also experience similar in-plane optical anisotropy, which tends to align along the axis of the quantum dot chain. Our optical and structural results show that InAs quantum dot chains could be a potential platform for nanophotonic waveguiding and integrated circuits.