Ultrafast sub-30-fs all-optical switching based on gallium phosphide

Grinblat, Gustavo; Nielsen, Michael P.; Dichtl, Paul; Li, Yi; Oulton, Rupert F. and Maier, Stefan A. (2019): Ultrafast sub-30-fs all-optical switching based on gallium phosphide. In: Science Advances, Vol. 5, No. 6, eaaw3262

Abstract

Gallium phosphide (GaP) is one of the few available materials with strong optical nonlinearity and negligible losses in the visible (lambda > 450 nm) and near-infrared regime. In this work, we demonstrate that a GaP film can generate sub30- fs (full width at half maximum) transmission modulation of up to similar to 70% in the 600- to 1000-nm wavelength range. Nonlinear simulations using parameters measured by the Z-scan approach indicate that the transmission modulation arises from the optical Kerr effect and two-photon absorption. Because of the absence of linear absorption, no slower free-carrier contribution is detected. These findings place GaP as a promising ultrafast material for all-optical switching at modulation speeds of up to 20 THz.

• Item Type: Journal article
• Faculties: Physics
• Subjects: 500 Science > 530 Physics
• ISSN: 2375-2548
• Language: English