Stable, highly nonlinear amorphous silicon nanowires with very low   nonlinear absorption
  The nonlinear characteristics of hydrogenated amorphous silicon nanowires are experimentally demonstrated. A high nonlinear refractive index, n2=1.19 x 10-17 m2/W, combined with a low two-photon absorption, 0.14 x 10-11 m/W, resulted in a high nonlinear FOM of 5.5. Furthermore, systematic studies over hours of operational time under 2.2W of pulse peak power revealed no degradation of the optical response. 
Luca Carletti, Christian Grillet, Phillipe Grossec, Badhise Ben-Bakir,   Sylvie Menezoc, Jean-Marc Fedelic, David J. Moss, a...
physics.optics