THz pulse measurement with a chirped optical beam

Electro-optic sampling is a powerful technique for the characterization of a repetitive electrical waveform, such as an electrical signal in an integrated circuit or a THz beam in a free-space environment. With the introduction of a chirped optical probe beam in the electro-optic sampling experiment it is finally possible to achieve a single-shot THz pulse measurement. Using a linearly chirped optical probe pulse in free-space electro-optic measurements, a temporal waveform of a co-propagating THz field is linearly encoded onto the frequency spectrum of the optical probe pulse, and then decoded by dispersing the probe beam from a grating to a detector array. We achieve acquisition of picosecond THz field pulses without using mechanical time-delay device. We also demonstrate a single-shot electro-optic measurement of the temporal waveform of a THz pulse.