Keywords:nanowire, III-V compound semiconductor
InP-based nanowire quantum dots (NW-QDs) utilizing InP/InAsP/InP axial heterostructure are expected for efficient single photon emitters in the telecommunication band. To date, we have confirmed single photon emission in the near-infrared regions from NW-QDs, and light emission in the telecommunication band from InAsP QDs controlling As/P composition. To further improve their performance for practical application, control and miniaturization of NW diameter are important to increase the reproducibility and to achieve strong lateral quantum confinement effect. In this study, we applied thermal etching of InP NWs grown by selective-area growth and miniaturized top diameter of InP NWs down to 20 nm. We also demonstrated InP/InAsP/InP NW-QDs using thermally etched InP NWs and confirmed sharper PL emission from exciton in QDs than that formed without thermal etching, which were ascribed to stronger quantum confinement effect and weaker spectral diffusion.