2022/08/18 by Swagata Bhunia, Bhunia, Swagata, Ritam Sarkar +9 · 1 citation
Engineering · Materials Science · Physics and Astronomy · #Applied Physics (physics.app-ph) #FOS: Physical sciences #Ga2O3 and related materials #GaN-based semiconductor devices and materials #Nanowire Synthesis and Applications
paper · pdf · doi:10.48550/arxiv.2208.08724
openalex publication_date 2022/08/18 · openalex created_date 2022/08/20 · openalex updated_date 2026/07/28
The nanowire-supported quantum dot (NWQD) of GaN is an unconventional nanostructure, which is extremely promising for realization of UV photonics in general, and room-temperature single photon generation, in particular. While GaN-NWQDs have several promising attributes, the crucial challenge in exploiting their full potential, is to reduce the lateral dimensions of the QDs, to the order of the exciton Bohr-radius in GaN. Also critical is to suppress the built-in electric field due to spontaneous and piezoelectric polarization, which adversely affects the radiative recombination lifetime. We report here the innovation of a simple yet powerful single-step epitaxial growth technique, to achieve both of these targets. By combining controlled and on-demand thermal decomposition of GaN nanowires, with our previously-developed strategy of inhibiting the same via AlN-capping, we demonstrate that the NWQD-diameter can indeed be reduced to the truly strong-quantum-confinement limit. In these ultra-scaled GaN QDs, we show that the built-in electric fields are almost completely suppressed. The NWQD fabrication-strategy developed in this work may pave the way for fabrication of highly efficient classical and quantum UV-emitters based on GaN.