Fig. 2: Device characterization using an electro-optic S21 measurement.
From: Ultra-low-noise microwave to optics conversion in gallium phosphide
a Setup for continuous conversion measurement. The device is driven by the output of a vector network analyzer (VNA). The mechanical mode is then read out using a CW laser which is red-detuned from the optical cavity by ~ωm. The reflected light is then recorded on a high-frequency photodiode and the signal fed back to the VNA. b Electro-optic conversion signal around 2.8 GHz. Red (blue) curve taken for nc = 142 (1665). In this electro-optic S21 spectrum, we can see two prominent modes at 2.790 GHz and 2.799 GHz. c Power-dependent electro-optic conversion signal. d Conversion linewidth for varying optical cavity photon number. Green (orange) points are for the mode at 2.799 (2.790) GHz. e Photon-number-dependent un-normalized optical output power for the same two modes.
