Chirp-independent time-resolved spectroscopy using the self-reference method

Abstract

We present a simple method for compensating a chirp of a white light continuum for femtosecond time-resolved spectroscopy. The quantity of the chirp was directly measured by referring to rising step of transient absorption time evolutions of a target material (polythiophene-fullerene thin organic blend film) itself. The analyzed chirp information in this manner was used for a correction procedure; each wavelength of the chirped white light continuum was correlated to an optical delay stage position for calibrating exactly with respective zero-delays. Consequently, it was possible to simultaneously measure both ultrafast kinetics and chirp independent time-resolved spectra with this method.