Extended Data Fig. 7: Numerical simulation of the cavity modes of the sodium-based plasmonic nanolaser.
From: Stable, high-performance sodium-based plasmonic devices in the near infrared
a, Measured emission spectra of the plasmonic nanolaser around the lasing threshold, which exhibit two clear cavity modes at wavelengths of 1,257Â nm and 1,343Â nm respectively. b, Spectrum profile of the two cavity modes, where the resonant wavelength and the linewidth are obtained from the simulation. We assumed Lorentz-shape spectrum profiles here. The simulation shows that the cavity modes at wavelengths of 1,257Â nm and 1,343Â nm can be identified as plasmonic whispering-galley modes with azimuthal orders of 15 and 14, respectively, and the corresponding quality factors Q of these two modes are 340 and 236, respectively. c, d, Top (c) and side (d) views of simulated electric-field distributions of the plasmonic whispering-galley modes with azimuthal order of 15. e, Electric-field profile E extracted from the white dashed line in d. f, g, Top (f) and side (g) views of simulated electric-field distributions of the plasmonic whispering-galley modes with azimuthal order of 14. h, Electric-field profile extracted from the white dashed line in g.
