We demonstrate the ability of single-subwavelength-size nanoapertures fabricated in a gold metal thin film to enhance second-harmonic generation (SHG) as compared to a bare metal film. Nonlinear microscopy imaging with polarization resolution is used to quantify the SHG enhancement in circular and triangular nanoaperture shapes. The dependence of the measured SHG enhancement on circular aperture diameters is seen to originate from both phase retardation effects and field enhancements at the nanoaperture edge. Triangular nanoapertures exhibit superior SHG enhancement compared with circular ones, as expected from their noncentrosymmetric shape.
© 2010 Optical Society of America
Original Manuscript: September 15, 2010
Manuscript Accepted: October 27, 2010
Published: November 30, 2010
Peter Schön, Nicolas Bonod, Eloïse Devaux, Jérôme Wenger, Hervé Rigneault, Thomas W. Ebbesen, and Sophie Brasselet, "Enhanced second-harmonic generation from individual metallic nanoapertures," Opt. Lett. 35, 4063-4065 (2010)