Tunable effective nonlinear refractive index of graphene dispersions during the distortion of spatial self-phase modulation
Citation:
Wang, G., Zhang, S., Umran, F.A., (...), Blau, W.J., Wang, J., Tunable effective nonlinear refractive index of graphene dispersions during the distortion of spatial self-phase modulation, Applied Physics Letters, 104, 14, 2014, 141909-Download Item:
1.4871092.pdf (PDF) 1.237Mb
Abstract:
Spatial self-phase modulation (SSPM) was observed directly when a focused He-Ne laser beam at 633 nm went through liquid-phase-exfoliated graphene dispersions. The diffraction pattern of SSPM was found to be distorted rapidly right after the incident beam horizontally passing through the dispersions, while no distortion for the vertically incident geometry. We show that the distortion is originated mainly from the non-axis-symmetrical thermal convections of the graphene nanosheets induced by laser heating, and the relative change of nonlinear refractive index can be determined by the ratio of the distortion angle to the half-cone angle. Therefore, the effective nonlinear refractive index of graphene dispersions can be tuned by changing the incident intensity and the temperature of the dispersions.
Sponsor
Grant Number
Science Foundation Ireland (SFI)
12/IA/1306
Author's Homepage:
http://people.tcd.ie/wblauDescription:
PUBLISHED
Author: BLAU, WERNER
Type of material:
Journal ArticleCollections:
Series/Report no:
Applied Physics Letters104
14
Availability:
Full text availableKeywords:
Spatial self-phase modulation (SSPM)DOI:
http://dx.doi.org/10.1063/1.4871092Licences: