Fig. 5: Characterization of Frequency Doubling Responses.
From: Single-chip silicon photonic engine for analog optical and microwave signals processing

a The engine configuration for RF frequency doubling. b Measurement setup for the nonlinear RF responses. c Configuration of the modulator block for high extinction ratio; d Frequency doubling results with off-chip PD; e Frequency doubling results with on-chip PD. EA Electronic Amplifier, EDFA Erbium-Doped Fiber Amplifier, ESA Electrical Spectrum Analyzer.