Compact Optical Spectroscopy: The Future of Food Analytics in Your Pocket
Anna G. Mignani, Institute of Applied Physics "Nello Carrara" (IFAC), CNR, Italy
Plasmonic Nanomaterials for Ultrafast Nonlinear Optics and Photochemistry
Anatoly Zayats, King's College London, United Kingdom
Optical and Electronic Fourier Surfaces
David J. Norris, ETH Zurich, Switzerland
Compact Optical Spectroscopy: The Future of Food Analytics in Your Pocket
Anna G. Mignani
Institute of Applied Physics "Nello Carrara" (IFAC), CNR
Italy
Brief Bio
Anna Grazia Mignani, a physicist by training, is a Research Director at the National Research Council of Italy (CNR), which she joined in 1984. Her early work focused on designing and experimenting with fiber optic sensors and networks for temperature and vibration monitoring. She then transitioned to spectroscopy-based sensors for environmental applications, particularly water monitoring. Her most recent research centers on spectroscopy for food applications, specifically multi-analysis of safety, quality, and nutraceutical indicators using a single light shot and multivariate processing of spectroscopic data.
Her work has been funded by European and national research grants in applied optical sensing, and she holds several US and EU patents. She has been a visiting scientist in laboratories in Belgium, Ireland, and China, and serves as an expert evaluator, project reviewer, and advisor for international funding agencies. An SPIE Fellow, she served on the SPIE Board of Directors from 2016 to 2018 and is currently a member of the AdCom of the IEEE Sensors Council.
From 2017 to 2022, she was seconded to Brussels as a National Expert at the European Research Council Executive Agency of the European Commission, working with the "Systems and Communication Engineering," "Condensed Matter Physics," and “Synergy” panels.
Abstract
Optical spectroscopy is a game-changer for food analysis, offering a cost-effective and eco-friendly alternative to traditional methods. With rapid, non-destructive measurements that eliminate the need for harmful chemicals and solvents, optical spectroscopy is revolutionizing green analytics for food quality and safety. Its minimal sample preparation saves time and resources, making it increasingly popular in the industry.
Moreover, by leveraging chemometrics or other AI algorithms to enhance the interpretation of complex data, optical spectroscopy allows for simultaneous analysis of multiple food components simultaneously. Just a quick light shot, combined with advanced spectroscopic training, provides comprehensive quantitative and qualitative assessments of various nutraceutical indicators all at once. It's a smart, sustainable way to ensure the best in food quality and safety.
While the mid-infrared band is known for its detailed molecular fingerprinting, the near-infrared (NIR) region is generating a buzz in food applications. This is where the absorption of overtones and combinations of molecular vibrations involving C-H, O-H, and N-H bonds occur, revealing crucial insights into food composition.
Photonic technologies initially developed for telecommunications, generated an explosion of compact light sources, detectors, micro-spectrometers, spectral sensors, fiber optics, and micro-photonic components. These innovations are now transforming food control, providing compact, robust, and low-cost instruments that are perfect for online applications by users with minimal technical training. This surge in new devices is driving a steady increase in NIR applications for food analysis.
In this talk, we'll explore the latest and most compact NIR spectroscopy devices, including pocket-sized and smartphone-connected models. We'll discuss their applications in food analysis and showcase their potential. Get ready to see how these powerful tools can revolutionize food quality and safety, and discover opportunities for future collaborations.
Plasmonic Nanomaterials for Ultrafast Nonlinear Optics and Photochemistry
Anatoly Zayats
King's College London
United Kingdom
Brief Bio
Professor Anatoly V. Zayats is a Chair in Experimental Physics and the head of the Photonics & Nanotechnology at the Department of Physics, King’s College London, where he also leads Nano-optics and Near-field Spectroscopy Laboratory (www.nano-optics.org.uk). He is a Co-Director of the London Centre for Nanotechnology and the London Institute of Advanced Light Technologies. His current research interests are in the areas of nanophotonics, plasmonics, metamaterials, optical spin-orbit coupling, plasmonically-derived hot carriers, scanning probe microscopy, nonlinear and ultrafast optics and spectroscopy, and optical properties of surfaces, thin films, semiconductors and low-dimensional structures. He is a founding Editor-in-Chief of Advanced Photonics journal. He is a Fellow of the Institute of Physics, the Optical Society of America, SPIE, the Royal Society of Chemistry and elected Member of Academia Europaea.
Abstract
Plasmonic nano- and meta-materials provide unique opportunities for engineering strong light-matter interactions enabling control over hot-carrier dynamics. The associated field enhancement and nonequilibrium carriers result in nonlinear optical effects important for controlling light with light and also induce photochemical transformations in the vicinity of nanostructures. Conventionally, nonlinear optical applications are limited by the available choice of naturally occurring materials and their generally weak nonlinear response. Weak nonlinearity of natural materials can be enhanced by their nanostructuring or using metamaterial approach. These can be addressed through material-level improvements, nanostructuring and leveraging the nuanced properties of nanostructured media combined with molecular species, in particular in a strong coupling regime. The nonlocal spatial dispersion effects are also important, offering opportunities for customizing the nonlinear response, particularly in the epsilon-near-zero regime. Quantum size effects in monocrystalline ultrathin plasmonic films have recently provided new opportunities for engineering both nonlinear optical response and hot-electron temporal response. Here, we will discuss plasmonic hetero-nanostructures for tailoring hot-electron dynamics, plasmonic nonlinearities, photocatalytic transformations and chiral response. Going beyond traditional field enhancement effects, we show how the introduction of additional hot-electron relaxation pathways, anisotropy and nonlocality allows to accelerate of decelerate temporal response of nonlinear optical effects in plasmonic nanostructures and improve the interaction of hot-carriers with molecular species resulting in enhanced photochemistry. The controlled ultrafast optical and electronic processes are important for applications in nonlinear photonics, photocatalysis and development of time-varying media.
Optical and Electronic Fourier Surfaces
David J. Norris
ETH Zurich
Switzerland
Brief Bio
David J. Norris received his B.S. in Chemistry from the University of Chicago in 1990. He then moved to MIT to complete his Ph.D. in physical chemistry under the guidance of Moungi Bawendi (1995). After an NSF postdoctoral fellowship with W. E. Moerner at the University of California, San Diego, he started his own research group at the NEC Research Institute in Princeton (1997). He then became an Associate Professor (2001–2006) and Professor (2006–2010) of Chemical Engineering and Materials Science at the University of Minnesota, where he also served as Director of Graduate Studies in Chemical Engineering (2004–2010). In 2010, he moved to ETH Zurich where he is currently Professor of Materials Engineering. From 2016 to 2019, he served as the Head of the Department of Mechanical and Process Engineering. He has received the Credit Suisse Award for Best Teacher at ETH, twice the Golden Owl Award for Best Teacher in his department, the Max Rössler Research Prize, an ERC Advanced Grant, and the ACS Nano Lectureship Award. He is a Fellow of the AAAS, APS, and Optica, and an editorial board member for ACS Applied Optical Materials, ACS Photonics, and Nano Letters. His research focuses on how materials can be tailored for new and useful optical properties.
Abstract
According to Fourier optics, the surface profile of an ideal diffraction grating should contain a precise sum of sinusoidal waves. However, because fabrication techniques typically yield profiles with only two depth levels, complex “wavy” surfaces cannot be obtained, limiting the straightforward design and implementation of sophisticated diffractive surfaces. Here, we eliminate this design–fabrication mismatch and produce optical surfaces with an arbitrary number of specified sinusoids, yielding previously unattainable diffractive surfaces including intricate two-dimensional moiré patterns, quasicrystals, and holograms. We then show that such patterns can be reduced to nanometer length scales, creating wavy Fourier surfaces for 2D electronics. Finally, we will discuss several ongoing efforts to exploit these optical and electronic surfaces in applications.