Clear energy level shift in ultranarrow InGaAs/InP quantum well wires fabricated by reverse mesa chemical etching

Abstract

We have fabricated ultranarrow InGaAs/InP buried quantum well wires by means of electron beam lithography and reverse mesa wet etching. Owing to the reverse mesa etching profile, the lateral dimension of the wires has been reduced to 10 nm. Furthermore, we investigated the optical characteristics of these wires by photoluminescence and observed, for the first time, clear dependence of luminescence wavelength upon the wire width even for wires down to 10 nm, which is well explained by the theoretical calculation. The blue-shifted shoulder structures were also observed and they were assigned theoretically to be the second quantized level.