Generation and detection of ultrashort electrical pulses using nonlinear optical techniques

Summary form only given. With the ongoing desire to characterize material and circuit properties in optoelectronic devices over increasingly larger frequency ranges, there is a strong need to reduce the duration of the probing electrical transients. We report the generation 170 fs fullwidth at half-maximum (FHWM) electrical pulses on a coplanar transmission line using a fully nonlinear optical approach. These are believed to be the shortest electrical pulses produced to date on a transmission line. Both the generation and detection processes utilize the nonresonant second-order susceptibility of a poled polymeric medium embedded within the optoelectronic device. Optical rectification is utilized for the generation process, while electro-optic sampling is used for detection. Of critical importance to the high-speed performance are the undercladding and overcladding layers in the device structure. These are used to significantly reduce radiation losses by reducing the dielectric mismatch.