Using optical absorption to reduce cross-talk in spatially multiplexed waveguiding metasurfaces.

Dual-wavelength metasurfaces often employ spatial multiplexing design concepts where two interleaved lattices of meta-atoms, each designed for a specific wavelength, occupy the same layer. However, this arrangement incurs efficiency losses as each wavelength inevitably "sees" unintended meta-atoms designed for the other wavelength, causing spurious interference (crosstalk) effects, which are especially affecting the shorter wavelength. In this paper, we numerically demonstrate that the crosstalk can be reduced by introducing some optical absorption at the shorter wavelength, unveiling the near-field mechanisms at play.

Dual-Resonance Nanostructures for Color Downconversion of Colloidal Quantum Emitters.

We present a dual-resonance nanostructure made of a titanium dioxide (TiO) subwavelength grating to enhance the color downconversion efficiency of CdZnSeS colloidal quantum dots (QDs) emitting at ∼530 nm when excited with a blue light at ∼460 nm. A large mode volume can be created within the QD layer by the hybridization of the grating resonances and waveguide modes, resulting in large absorption and emission enhancements. Particularly, we achieved polarized light emission with a maximum photoluminescence enhancement of ∼140 times at a specific angular direction and a total enhancement of ∼34 times within a 0.

Investigating receptor-mediated antibody transcytosis using blood-brain barrier organoid arrays.

Background: The pathways that control protein transport across the blood-brain barrier (BBB) remain poorly characterized. Despite great advances in recapitulating the human BBB in vitro, current models are not suitable for systematic analysis of the molecular mechanisms of antibody transport. The gaps in our mechanistic understanding of antibody transcytosis hinder new therapeutic delivery strategy development.

Silicon Nanoantenna Mix Arrays for a Trifecta of Quantum Emitter Enhancements.

Dielectric nanostructures have demonstrated optical antenna effects due to Mie resonances. Previous work has exhibited enhancements in absorption, emission rates and directionality with practical limitations. In this paper, we present a Si mix antenna array to achieve a trifecta enhancement of ∼1200-fold with a Purcell factor of ∼47.

Introduction of a model of skin lesions on rats and testing of dissolving microneedles containing 5-aminolevulinic acid.

Topical photodynamic therapy (PDT) is widely used to treat non melanoma skin cancers. It consists of topically applying on the skin lesions a cream containing a prodrug (5-aminolevulinic acid (5-ALA) or methyl aminolevulinate (MAL)) that is then metabolized to the photosensitizer protoporphyrin IX (PpIX). Light irradiation at PpIX excitation wavelength combined with oxygen then lead to a photochemical reaction inducing cell death.