Temporal characterization of two-octave infrared pulses by frequency resolved optical switching

Abstract We present the temporal characterization of infrared pulses with spectra extending from 0.55 to 2.5 μ m by using frequency resolved optical switching (FROSt) technique. The are obtained broadening femtosecond at 1.75 central wavelength in a two-stage hollow core fiber setup. This work demonstrates capability FROSt technique temporally characterize ultra-broadband spectra. Being free phase-matching constraints, it enables very low energy limit detection threshold and arbitrary long pulse duration. strength is illustrated supercontinua whose span over two octaves only 150 nJ that spread almost 40 ps. capabilities provide versatile tool for sub-cycle study nonlinear processes such as supercontinuum generation.