Lasers, Optics & Photonics

Plasmonic metamaterials at optical frequencies can be used to manipulate the local photonic density of states and tailor the spectrum purposefully and  electively. Here nano-patterned hyperbolic metamaterials (HMM) for high- requency quantum dots single photon source (SPS) will be presented. Nanowire quantum dots fabricated by top-down method or selective area grown can obtain electrically driven site-controlled SPS, which is promising for integrated chip-scale SPS. However, considering the quantum confinement effect in quantum dots, the diameter of the nanowire is often less than 50 nm, which shows weak photon confinement and low spontaneous emission rate. HMM shows hyperbolic dispersion and corresponds to infinite local photonic density of states, which can be used for broadband Purcell effect radiative decay engineering. But due to the non-radiative behaviour of plasmonic modes in HMM, most of the emission photon will dissipate inside the metamaterial due to ohmic losses in planar HMM. Here we propose a nano-patterned hyperbolic metamaterials for nanowire quantum dots SPS. Combining the broadband enhancement of spontaneous emission from HMM and directional light extraction enhancement from nano-patterned scattering structures, broadband enhancements of both spontaneous emission rate and photon extraction efficiency were demonstrated over the whole visible range. Our research provides a novel idea for high-frequency and high-brightness nanowire quantum dots SPS, which has good prospect in many applications such as quantum information processing.