{"title":"Geometric Sensitivity of Mode Hybridization in Symmetric and Asymmetric Nanoscale Dimers.","authors":"D Keith Roper, Ricardo R Romo","doi":"10.1109/nmdc58214.2024.10894519","DOIUrl":"10.1109/nmdc58214.2024.10894519","url":null,"abstract":"<p><p>Nanoparticles exhibit optical and infrared sensitivity useful in optoelectronics, spectroscopy, and sensing. Capacitative and conductive coupling induces dipolar and charge transfer plasmon modes in nanoscale dimers. Optical and infrared activity of these hybridized modes are exquisitely sensitive to geometric features of the nanoscale dimer. This study examined spectra for 7 to 8-nanometer dimers with symmetric or asymmetric radii using discrete dipole approximation. Variations in optical and infrared activity were attributable to field localization due to geometry-induced hybridization. Methods herein are useful guides to design dimers for optoelectronic, spectroscopic, and sensing applications.</p>","PeriodicalId":521039,"journal":{"name":"... IEEE Nanotechnology Materials and Devices Conference. IEEE Nanotechnology Materials and Devices Conference","volume":"2024 ","pages":"9-14"},"PeriodicalIF":0.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12416501/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145031705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Hyperspectral Analysis of Enhanced Extinction in Micrometer-Thin Polymer Films containing Nanoparticles at High Volume Fraction.","authors":"D Keith Roper","doi":"10.1109/nmdc58214.2024.10894700","DOIUrl":"10.1109/nmdc58214.2024.10894700","url":null,"abstract":"<p><p>Extinction in thin polymer films containing nanoparticles is important to photovoltaics, sensors, and interconnects. Extinction measured in 1-millimeter-thin films containing plasmonic nanoparticles increased with nanoparticle density to levels higher than predicted. Yet, enhancement of extinction was not measured in <100-nanometer-thin films containing high-density plasmonic nanoparticles. The present study examined extinction in 80 micrometer films that contained plasmonic nanoparticles at increasing volume fractions. Optical images and spectra were integrated in a new hyperspectral method to quantitate visual attributes to use nanoparticle-containing films in e.g., colorimetric assays. Measured extinction was compared with values predicted by the exact Mie solution to Maxwell's equation and by the Maxwell-Garnett effective medium theory. Extinction measured in 80-micron films was found to increase with nanoparticle volume fraction from a low value predicted by Mie theory to a high value predicted by Maxwell-Garnett effective medium theory. Results of the present study are useful to specify the volume fraction of nanoparticles in thin polymer films to obtain desired spectral characteristics for photovoltaics, sensors, interconnects, and colorimetric point-of-care assays.</p>","PeriodicalId":521039,"journal":{"name":"... IEEE Nanotechnology Materials and Devices Conference. IEEE Nanotechnology Materials and Devices Conference","volume":"2024 ","pages":"123-128"},"PeriodicalIF":0.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12416504/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145031698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Perceived Color Difference of Nanoscale Spheroids in Colorimetry due to Dipolar Modes.","authors":"D Keith Roper","doi":"10.1109/nmdc58214.2024.10893974","DOIUrl":"10.1109/nmdc58214.2024.10893974","url":null,"abstract":"<p><p>Nanoparticle labels enable colorimetric point-of-care devices for rapid, low-cost diagnosis and health monitoring. Accurate interpretation of colorimetric assays relies on reliable perception of differences in quantitative color attributes such as hue, chromaticity, and saturation. This study examined interactions between physical factors such as nanoparticle shape, illumination, and sample environment, and biological factors affecting color vision deficit and optical signal processing that influenced perceived color difference. Comparing measurements and simulation supported a rational framework to design and implement nanoscale spheroids that maximized perceptual color differences for both normal and colorblind observers in colorimetric biomedical point-of-care assays.</p>","PeriodicalId":521039,"journal":{"name":"... IEEE Nanotechnology Materials and Devices Conference. IEEE Nanotechnology Materials and Devices Conference","volume":"2024 ","pages":"57-62"},"PeriodicalIF":0.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12416505/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145031701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}