Simultaneous self-phase modulation and two-photon absorption measurement by a spectral homodyne Z-scan method.
We developed a technique to simultaneously measure self-phase modulation and two-photon absorption using shaped femtosecond laser pulses. In the conventional Z-scan measurement technique the amount of nonlinearity is determined by measuring the change in shape and intensity of a transmitted laser beam. In contrast, our method sensitively measures nonlinearity-induced changes in the pulse spectrum. In this work we demonstrate the technique in nonlinear absorptive and dispersive samples, quantify the obtained signal, and compare the measurements with traditional Z-scans. This technique is capable of measuring these nonlinearities in highly scattering samples.
Department of Chemistry, Duke University, Durham, NC 27708, USA. Martin.Fischer@duke.edu
Martin C
MC
Fischer
Henry C
HC
Liu
Ivan R
IR
Piletic
Warren S
WS
Warren
D003198:Computer Simulation; D008962:Models, Theoretical; D055095:Optics and Photonics; D017785:Photons; D012542:Scattering, Radiation; D012815:Signal Processing, Computer-Assisted