Fig. 3: PL spectra for cavities without and with defects.
From: Low-threshold topological nanolasers based on the second-order corner state
a PL spectra of defect-free cavities with the parameters of a=380nm, D=242nm and g=50nm. b PL spectra of cavities with different numbers of defects, as shown in the inset. The numbers represent the number of missing square holes in the bulk of the PhC. Here, the missing square holes are several periods away from the corner. The PL spectra are shifted for clarity
