High-speed electrical sampling using optical second-harmonic generation

We report the application of optical second-harmonic generation to the measurement of ultrafast electrical pulses. The technique relies on the sensitivity of the second-harmonic response to electric fields in centrosymmetric materials. Electrical pulses propagating on a silicon-based coplanar transmission line have been characterized with subpicosecond time resolution and 100 mV/√Hz sensitivity. We have measured the bias dependence of the second harmonic intensity over a 20 V range and have used this data to calibrate the transient response. The observed full-width at half maximum response time of the SHG waveform is ≃1 ps, which is consistent with the value obtained from an electronic cross-correlation measurement. © 1996 American Institute of Physics.