Microphotoluminescence perpendicular to the growth direction of quantum nanostructures

Abstract

Our research team has achieved the lateral collection of micro-photoluminescence from single quantum dots. This is done via optic fibres inserted into V-grooves etched to precisely the right depth to match the fibre core to the nanostructure. The depth can be controlled to within half a micron allowing consistent signal collection with a fibre of core diameter 4 μm. The V-groove is defined by e-beam lithography so can be positioned laterally with 20 nm accuracy with respect to the device. Other than the V-groove the top surface is left available for further processing. The technique has allowed magneto-photoluminescence experiments to be performed laterally on single quantum dots with resolution of the spin fine structure of the exciton and a high energy biexciton.