Extended Data Fig. 4: Device parameter analysis.
From: High-efficiency and broadband on-chip electro-optic frequency comb generators
a, b, Transmission spectrum of a single cavity 1 (a) and 2 (b) with the same fabrication parameters as the coupled-resonator device. c, Transmission spectrum of a coupled-resonator device on the through port. d, Transmission spectrum of a coupled-resonator device when microwave is on. (c) and (d) are measured on two different coupled-resonator devices with the same fabrication parameters. The background oscillation is due to the Fabry-Perot resonance formed in the bus waveguide due to the reflection at the two facets of the chip. The extracted parameters give a theoretical conversion efficiency of 28%.
