Enhancing the photoluminescence properties of single epitaxial gaas quantum dots using optical antennas

The authors have experimentally investigated the influence of plasmon resonant nanoantennas on the photoluminescence properties of individual epitaxial semiconductor quantum dots. As nanoantennas, a chemically synthesized spherical gold nanoparticles and lithographically fabricated structures were used. The emitters are epitaxially grown AlGaAs/GaAs quantum dots which are buried a few nanometers beneath the semiconductor surface and photoluminescence at approximately 760 nm wavelength. The advantage of this system is that the optical properties of the quantum dots are very stable and the transition dipole moments have a fixed orientation. The thin barrier layer allows efficient coupling between the quantum dot and an optical antenna positioned above the emitter. The position of a quantum dot can be determined with high precision from a characteristic feature in the surface topography above each quantum emitter using atomic force microscopy (AFM) or scanning electron microscopy.