picosecondenrange

Picosecond range refers to time intervals on the order of 10^-12 seconds. In ultrafast optics and photonics, picosecond pulses are generated by mode-locked lasers and related pulse-shaping techniques. The range is longer than femtoseconds and shorter than nanoseconds, with typical pulse durations from about 1 ps up to a few hundred ps.

Most picosecond pulses are produced by mode-locked solid-state or fiber lasers, using passive or active stabilization. Pulses in the picosecond domain often require dispersion management and spectral broadening to achieve short durations; pulse compression using grating or prism pairs, or chirped-pulse amplification, is common to reach the desired width. Energies span from picojoules to nanojoules, and repetition rates range from several megahertz to tens of gigahertz. Central wavelengths vary with the gain medium, from visible to near-infrared.

Characterization relies on ultrafast metrology such as autocorrelation, cross-correlation, and frequency-resolved optical gating to determine pulse duration and phase. Techniques use fast photodiodes, streak cameras, or spectrally resolved methods to retrieve timing and chirp. In fiber systems, dispersion and nonlinear effects can distort pulses and require careful compensation.

Applications include time-resolved spectroscopy and pump–probe experiments, semiconductor and chemical dynamics, microfabrication with controlled heat input, high-data-rate optical communication research, and biomedical imaging where short pulses enable nonlinear processes with reduced sample damage.