Latest article: enhanced second harmonic generation on nanoapertures

7 Décembre 2010 , Rédigé par JW Publié dans #Recent research work

My team has recently published a study on second harmonic generation on single gold nanoapertures. This was released in the December 1st issue of Optics Letters. You can find a free reprint here.

Metal nanostructures are interesting emitters for second harmonic generation (SHG) radiation, which occurs essentially from the non-centrosymmetry breaking at the metal-medium interface for objects of the order of 50nm-100nm size.
At MOSAIC 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.

This study has two main results:
* The SHG enhancement on circular nanoapertures is demonstrated to originate from both phase retardation effects and field enhancements at the aperture edge.
* Triangular nanoapertures exhibit superior SHG enhancement compared with circular ones, as expected from their noncentrosymmetric shape.