Fig. 1
From: A single-photon source based on topological bulk cavity
Design of the single-photon source based on a topological bulk cavity. a Schematic of the single-photon source, featuring a single quantum dot (QD) coupled to a ‘Q’-shaped topological bulk cavity. Inset: Unit cells of trivial and non-trivial PCs. b Band structures of the topological trivial (left panel) and non-trivial (right panel) PCs, where a = 420 nm, b = 123 nm, R1 = 0.97×a/3, and R2 = 1.048×a/3. The hybridization between p and d bands is indicated by the color scale. Inset: p and d modes with opposite parities at Γ points of the lower bands in these two PCs. c Simulated near-field (left panel) and angle-resolved far-field (right panel) distribution of dipole-like bulk state in the ‘Q’-shaped cavity. White lines in the left panel indicate the topological interface. Solid and dashed circles in the right panel indicate the light cone and NA ( = 0.9) of the collection objective, respectively. The eigen-frequency of the bulk state is displayed by dashed lines in Fig. 1b
