Fig. 4: Experimental vortex and anti-vortex nanolasers.
From: Vortex nanolaser based on a photonic disclination cavity
a,b, Scanning electron microscopy images of fabricated photonic disclination cavities with the expanded core (a; vortex) and shrunken core (b; anti-vortex). Scale bars, 500 nm. c–e, Measured above-threshold PL spectra and L–L curves (insets) from the cavities of a (c) and b (d and e). The peak wavelengths and lasing thresholds are 1,533.3 nm and 80 μW (c), 1,535.4 nm and 412 μW (d) and 1,536.4 nm and 346 μW (e), respectively. The spectra in d and e are from doubly degenerate modes. f–h, Measured polarization-resolved lasing images from the cavities of a (f) and b (g and h). The mode profiles were captured after placing a linear polarizer in front of the IR camera (Methods). White arrows indicate the directions of the linear polarizer: 0°, 45°, 90°. Images captured without a linear polarizer are shown in the top left panels. Scale bars, 3 μm.
