About Nonlinear Optics Group

The group, founded in 1987, is directed by Dr. Eric Van Stryland, Dr. David Hagan, and Dr. M.J. Soileau.

The NLO group works at measuring and understanding the interaction of high irradiance light with matter, focusing on semiconductors and organic materials and investigating how to enhance nonlinear interactions using engineered materials (e.g. quantum wells and dots) and nanoparticles with local field enhancement. The group has invented a number of new techniques for characterizing the nonlinear optical properties of materials, e.g. Z-scan, white-light continuum Z-scan, and nonlinear Beam Deflection and has pioneered advances in the understanding of the nonlinear interactions, e.g. developed nonlinear Kramers-Kronig relations linking ultrafast nonlinear refraction to nonlinear absorption (e.g. two-photon absorption). The group also pioneered developments in cascaded second-order nonlinearities (e.g. second-harmonic generation) which mimic themselves as ultrafast nonlinear absorption and refraction. Work is currently underway in Extremely Nondegenerate Nonlinear Photonics in semiconductors where orders of magnitude enhancement of nonlinearities occurs allowing IR detection with wide-gap semiconductors and the possibility of 2-photon gain and lasing. The group has graduated more than 40 students, of which 33 have obtained the title of PhD.