Enabling High Precision Gradient Index Control in Subsurface Multiphoton Lithography.

Multiphoton lithography inside a mesoporous host can create optical components with continuously tunable refractive indices in three-dimensional (3D) space. However, the process is very sensitive at exposure doses near the photoresist threshold, leading previous work to reliably achieve only a fraction of the available refractive index range for a given material system. Here, we present a method for greatly enhancing the uniformity of the subsurface micro-optics, increasing the reliable index range from 0.

Absorbance amplification using chromophore-nanoplasmon coupling for ultrasensitive protein quantification.

A plasmonic nanoscale Lycurgus cup array (nanoLCA), via near-field interaction with chromophores in commercial colorimetric biochemical assays, can drastically enhance assay sensitivity by over 2 orders of magnitude. A 96-microwell plate modified by placing the plasmonic nanoLCA on the well-bottom was used with the commercial Bradford protein quantification assay. Plasmons on the nanoLCA serve as an energy donor to matched resonance chromophores, and the near-field plasmonic energy coupling effect results in an increase in absorbance value at the plasmonic resonance wavelength.