Toward Nanometer-Scale Optical Photolithography:  Utilizing the Near-Field of Bowtie Optical Nanoantennas

Abstract

Optically resonant metallic bowtie nanoantennas are utilized as fabrication tools for the first time, resulting in the production of polymer resist nanostructures <30 nm in diameter at record low incident multiphoton energy densities. The nanofabrication is accomplished via nonlinear photopolymerization, which is initiated by the enhanced, confined optical fields surrounding the nanoantenna. The position, size, and shape of the resist nanostructures directly correlate with rigorous finite-difference time-domain computations of the field distribution, providing a nanometer-scale measurement of the actual field confinement offered by single optical nanoantennas. In addition, the size of the photoresist regions yields strong upper bounds on photoacid diffusion and resist resolution in SU-8, demonstrating a technique that can be generalized to the study of many current and yet-to-be-developed photoresist systems.

Plasmon-enhanced photocurrent generation and water oxidation from visible to near-infrared wavelengths

“…[15][16][17][18][19] Therefore, it is understood that metallic nanostructures act as photoelectric conversion systems that enable the effective utilization of photons, having a role similar to that of chlorophyll in photosynthesis. [20][21][22][23] Although many photoelectric conversion systems using LSPR have been previously reported, the wavelengths at which photoelectric conversion occurs did not extend beyond 700 nm, [24][25][26][27][28][29][30][31] creating a need to explore photoelectric conversion at infrared wavelengths past 800 nm.…”

Regioselective Localization and Tracking of Biomolecules on Single Gold Nanoparticles

“…This intensity dependence is exploited in case of MPPL wherein the field enhancement of the AuNT amplifies the energy at the tips, resulting in an enhanced energy density within these regions that exceeds the threshold exposure ( Figure 1 ). 17 …”

“…A consequence of the interaction is the ability to concentrate light fields with orders of magnitude enhancement at visible and near infrared (NIR) wavelengths to the subwavelength scale. Such enhancements find profound applications in improving the efficiencies of several phenomena such as fluorescence,1, 2, 3 surface‐enhanced Raman spectroscopy (SERS),4, 5, 6, 7, 8 surface‐enhanced infrared absorption,9, 10, 11 single‐molecule detection,12, 13 nonlinear optical effects,14, 15, 16 and multiphoton polymerization 17, 18. Exploiting this highly confined optical field is crucial, but simultaneously it is also challenging to position the desired molecules or particles accurately at these locations.…”

Molecular recognition with nanostructures fabricated by photopolymerization within metallic subwavelength apertures

“…This effect has been successfully applied to ultrahigh sensitivity optical biosensing 8,9 and nanometer-scale photopolymerization. [10][11][12] Metallic subwavelength apertures (MSAs) 13 are particularly appealing because of their geometrical simplicity and the possibility of being reliably and uniformly mass-produced through lithographic means, 14,15 allowing massive parallelism. An outstanding demonstration of light connement inside MSAs was the achievement of single molecule detection by uorescence correlation spectroscopy at biologically relevant concentrations.…”