Second harmonic generation from centrosymmetric arrays of gold nanoparticles

Nonlinear Optical Response from Arrays of Au Bowtie Nanoantennas

“…The total size of the scanned area was determined to be ∼29 μm × 29 μm. For all measurements shown here, the average power was kept constant at 10 mW (peak power density ∼10 12 W/cm 2 , peak fluence ∼32 mJ/cm 2 ) and each measurement was collected from an unexposed area of the arrays with total exposure times (autofocus + acquisition) of less than 120 s. While other studies of similar coupled-dimer nanostructures typically involve intensities several orders of magnitude smaller than those used here, ,− ,,,, we have experimentally determined our damage threshold to be 10 min at 25 mW (measured at the sample) by visual inspection of postirradiation SEM images of the BNAs. In addition, a test for optical damage at an average power of 10 mW exhibited remarkable signal stability for over an hour of irradiation.…”