Strong Zero-Phonon Transition from Point Defect-Stacking Fault Complexes in Silicon Carbide Nanowires

Nano Lett. 2021 Nov 10;21(21):9187-9194. doi: 10.1021/acs.nanolett.1c03013. Epub 2021 Oct 22.

Abstract

Crystallographic defects such as vacancies and stacking faults engineer electronic band structure at the atomic level and create zero- and two-dimensional quantum structures in crystals. The combination of these point and planar defects can generate a new type of defect complex system. Here, we investigate silicon carbide nanowires that host point defects near stacking faults. These point-planar defect complexes in the nanowire exhibit outstanding optical properties of high-brightness single photons (>360 kcounts/s), a fast recombination time (<1 ns), and a high Debye-Waller factor (>50%). These distinct optical properties of coupled point-planar defects lead to an unusually strong zero-phonon transition, essential for achieving highly efficient quantum interactions between multiple qubits. Our findings can be extended to other defects in various materials and therefore offer a new perspective for engineering defect qubits.

Keywords: Debye−Waller factor; nanowire; point defect; silicon carbide; stacking fault.