Lasing of CdSe/SiO2 nanocables synthesized by the facile chemical vapor deposition method

Abstract

Semiconductor nanocables are good candidates for developing robust and environmental stable nanolasers. In this work, high-quality CdSe/SiO₂ nanocables were synthesized by the facile chemical vapor deposition method. The as-synthesized nanocables were characterized by scanning electron microscopy, high-resolution transmission electron microscopy, and energy-dispersive X-ray spectroscopy. The results confirm that the cores in the nanocables are single crystalline hexagonal CdSe nanowires (NWs) with the growth direction of [0001], and the shells are amorphous SiO₂. Room-temperature lasing properties of single nanocables were reported for the first time by fabricating the nanocables into Fabry-Pérot cavities. The finite element method was employed to simulate the electromagnetic field distributions inside and outside the nanocable optical resonant cavities. Both the theoretical and experimental results show that there exists a strong dependence of the photonic mode confinement on the core diameter of the nanocable.