Fig. 3: Topological microcavity and gain medium.
From: Perovskite quantum dot one-dimensional topological laser
a Cross-sectional scanning electron microscope (SEM) image of the 1D microcavity consisting of 20 alternating layers of TiO2 and SiO2 and on each side of the interface. b Measured transmission spectrum of the 1D topological cavity. The high-Q transmission peak (Q~2000) at 507.3 nm, arising from the interface state, is magnified in the inset. c Room temperature photoluminescence spectrum of the CsPbBr3 quantum dots film deposited on PC1. The insets show a photograph of the film on PC1 under UV lamp illumination and a transmission electron microscope image of the cuboid CsPbBr3 quantum dots, with an average size of 9 nm.
