Fig. 3: Experimental setup and recorded transmission plots.
From: Efficient excitation and control of integrated photonic circuits with virtual critical coupling
a Schematic of the experimental setup to control the complex frequency of excitation via an electro-optic modulator (EOM) and detect the transmitted signals with high temporal resolution through a fast oscilloscope (30 GHz), while monitoring the averaged transmission with a slow oscilloscope. PD photodetector, OSC oscilloscope, and EDFA erbium-doped fiber amplifier. b Sequence of input \({I}_{input}\) and output \({I}_{output}\) intensities for various pulse time constants. The energy stored in the resonator during the pulse decays partly into the bus waveguide and is observed as a sharp peak once the pulse ends. c Intensity transmission \(T={I}_{output}/{I}_{input}\) for virtual undercoupling (red, \({\tau }_{in}=55ps\)), virtual critical coupling (blue, \({\tau }_{in}=138ps\)), and virtual overcoupling (green, \({\tau }_{in}=266ps\)). d Measured intensity relative transmission in the quasi-steady state before switching off the pulse (vertical dashed line in Fig. 3c) as a function of \({\tau }_{in}\); the inset shows the theoretical value of the transmission in the quasi-steady state \({T}_{qss}\) for the same cavity parameters.
