A new plasmonic configuration is proposed for application in a sensor and demonstrated for the detection of variations in the bulk refractive index of solutions. The configuration consists of monitoring two diffracted orders resulting from the interaction of a TM-polarized optical beam incident on a grating coupler, operating based on an effect termed the "optical switch". The two monitored diffracted orders enable differential measurements which cancel the drift and perturbations common to both, leading to an improved detection limit, as demonstrated experimentally. The measured switch pattern associated with the grating coupler is in good agreement with theory. Bulk sensing is demonstrated under intensity interrogation via the sequential injection of solutions comprised of glycerol in water into a fluidic cell. A limit of detection of about 10-6 RIU was achieved. The optical switch configuration is easy to implement and is cost-effective, yielding a highly promising approach for the sensing and the real-time detection of biological species.
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http://dx.doi.org/10.3390/s23031188 | DOI Listing |
Ophthalmic Physiol Opt
January 2025
School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia.
Purpose: To assess the repeatability of lipid layer thickness (LLT) measurement using the LipiView® interferometer after daily disposable contact lens (CL) wear and correlation with ocular comfort in soft contact lens wearers.
Methods: A prospective study was conducted over two consecutive months, wherein CL wearers (n = 20) wore either Somofilcon A or Verofilcon A daily disposable CLs in a crossover design, switching lenses after 1 month. The pre-corneal tear film LLT was measured at the end of each month after CLs had been worn for at least 6 h.
Importance: For myopia control to be beneficial, it would be important that the benefit of treatment (slowed eye growth) is not lost because of faster than normal growth (rebound) after discontinuing treatment.
Objective: To determine whether there is a loss of treatment effect (rebound) after discontinuing soft multifocal contact lenses in children with myopia.
Design, Setting, And Participants: The Bifocal Lenses in Nearsighted Kids 2 (BLINK2) cohort study involved children with myopia (aged 11-17 years at BLINK2 baseline) who completed the BLINK Study randomized clinical trial.
Nanotechnology
January 2025
Department of Physics, Shanghai Jiao Tong University, 800 Dong Chuan Road, Minhang Area, Shanghai 200240, Shanghai, 200240, CHINA.
Both stability and multi-level switching are crucial performance aspects for resistive random-access memory (RRAM), each playing a significant role in improving overall device performance. In this study, we successfully integrate these two features into a single RRAM configuration by embedding Ag-nanoparticles (Ag-NPs) into the TiN/Ta2O5/ITO structure. The device exhibits substantially lower switching voltages, a larger switching ratio, and multi-level switching phenomena compared to many other nanoparticle-embedded devices.
View Article and Find Full Text PDFLight Sci Appl
January 2025
Spin-Optics laboratory, St. Petersburg State University, St. Petersburg, 198504, Russia.
We introduce a novel neuromorphic network architecture based on a lattice of exciton-polariton condensates, intricately interconnected and energized through nonresonant optical pumping. The network employs a binary framework, where each neuron, facilitated by the spatial coherence of pairwise coupled condensates, performs binary operations. This coherence, emerging from the ballistic propagation of polaritons, ensures efficient, network-wide communication.
View Article and Find Full Text PDFBiomed Opt Express
January 2025
Department of Electronic Engineering, Maynooth University, Maynooth, Co. Kildare, Ireland.
Optical diffraction tomography enables label-free, 3D refractive index (RI) imaging of biological samples. We present a novel, cost-effective approach to ODT that employs a modular design incorporating a self-reference holographic capture module. This two-part system consists of an illumination module and a capture module that can be seamlessly integrated with any life-science microscope using an automated alignment protocol.
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