Fourier transform second harmonic generation for high-resolution nonlinear spectroscopy

Abstract In this communication we demonstrate a new characterization technique combining Fourier transform (FT) spectroscopy and second harmonic generation (SHG) that enables high spectral resolution with broadband femtosecond laser pulses. The strong and narrow exciton resonances of the wide band gap semiconductor ZnO were chosen for demonstrating the capabilities of the method. FT-SHG offers high reproducibility and high spectral resolution within the bandwidth of the input pulse.