ACTIVE AND NONLINEAR-WAVE PROPAGATION DEVICES IN ULTRAFAST ELECTRONICS AND OPTOELECTRONICS

We describe active and nonlinear wave propagation devices for generati on and detection of (sub)millimeter wave and (sub)picosecond signals. Shock-wave nonlinear transmission lines (NLTL's) generate approximatel y 4-V step functions with less than 0.7-ps fall times. NLTL-gated samp ling circuits for signal measurement have attained over 700-GHz bandwi dth. Soliton propagation on NLTL's is used for picosecond impulse gene ration and broadband millimeter-wave frequency multiplication. Picosec ond pulses can also be generated on traveling-wave structures loaded b y resonant tunneling diodes. Applications include integration of photo detectors with sampling circuits for picosecond optical waveform measu rements and instrumentation for millimeter-wave waveform and network ( circuit) measurements both on-wafer and in free space. General propert ies of linear and nonlinear distributed devices and circuits are revie wed, including gain-bandwidth limits, dispersive and nondispersive pro pagation, shock-wave formation, and soliton propagation.