Traditional Foods From Maize (Zea mays L.) in Europe

Maize (Zea mays L.) is one of the major crops of the world for feed, food, and industrial uses. It was originated in Central America and introduced into Europe and other continents after Columbus trips at the end of the 15th century. Due to the large adaptability of maize, farmers have originated a wide variability of genetic resources with wide diversity of adaptation, characteristics, and uses. Nowadays, in Europe, maize is mainly used for feed, but several food specialties were originated during these five centuries of maize history and became traditional food specialties. This review summarizes the state of the art of traditional foodstuffs made with maize in Southern, South-Western and South-Eastern Europe, from an historic evolution to the last research activities that focus on improving sustainability, quality and safety of food production

Real-Time 3D Visualization of the Formation of Micrograting Structures Upon Direct Laser Interference Patterning of Ge

10 pags., 8 figs., 1 tab. -- Correction added on August 11th, 2023 after first online publication: The spelling of the second author’s last name was corrected from “de Ruiz de Galarreta” to “Ruiz de Galarreta” and the formatting of equations 4–6 was fixed.Direct Laser Interference Patterning (DLIP) is a versatile technique that enables the fabrication of periodic micro- to nanometric scale structures over large areas in a variety of materials. The periodically modulated excitation pattern can be exploited to trigger a range of complex processes, including heating, melting, ablation, and matter reorganization. In this work, a novel strategy is developed to combine deep-ultraviolet (UV) DLIP (λ = 193 nm, τ = 23 ns) and real-time optical reflectivity and diffraction techniques to unravel the formation dynamics of grating structures with periods down to Λ = 740 nm. Applied to crystalline Ge wafers, single-pulse topography modulation profiles with amplitudes up to 85 nm can be imprinted. Moreover, the dynamics of the melting and solidification processes, as well as the surface topography deformation, can be followed in real-time. Combined with a model, changes in topography over time with ns resolution can be obtained. The results unambiguously reveal that the formation process of the 3D structures can only be understood when taking both Marangoni convection and thermocapillary waves into account. The technique presented here has the potential to unravel the formation dynamics of a wide range of periodic structures in other materials.This work has been partly funded by the national research grant ULS_PSB (PID2020-112770RB-C21) from the Spanish Research Agency (AEI, Ministry of Research and Innovation) and the European Regional Development Fund (ERDF), as well as by research grant HyperSolar (TED2021-130894B-C22) funded by the Recovery and Resilience Facility of the EU. C.R. acknowledges a Margarita Salas grant from the Universidad Autónoma de Madrid (CA1/RSUE/2021-00829) funded by the “Next Generation EU” program of the EU.Peer reviewe

Video de la conferencia "Componentes ópticos y fotónicos: desde la lente hacia las metasuperficies ópticas" impartida por Carlota Ruiz de Galarreta Fanjul durante el Día Internacional de la Luz 2021

Video de la conferencia "Componentes ópticos y fotónicos: desde la lente hacia las metasuperficies ópticas" impartida por Carlota Ruiz de Galarreta Fanjul durante el Día Internacional de la Luz 202

Filtering and Modulation from the Infrared to the Terahertz using Phase-Change Extraordinary Optical Transmission Metasurfaces

7 pags., 9 figs., 1 tab.Periodic arrays of sub-wavelength-scale holes in plasmonic metal films are known to provide resonant transmission peaks via the extraordinary optical transmission (EOT) effect. Active control of the spectral position of such transmission peaks can be obtained by adding a layer of phase-change material (PCM) to the EOT device. Switching the PCM layer between its amorphous and crystalline states can shift the spectral position of the resonance, enabling potential applications in the fields of active filtering and sensing (e.g., multispectral sensing), and for signal modulation. Here, the design, fabrication, and characterization of active EOT devices are targeted at various important regions of the optical spectrum.Funding support is gratefully acknowledged from the EPSRC-QinetiQ TEAM-A Prosperity Partnership grant (EP/R004781/1), and from the EPSRC CDT in Metamaterials (EP/L015331/1). Thanks are also due to the various University of Exeter colleagues, in particular Dr. Liam Trimby, Dr. Santiago Garcia-Cuevas Carrillo, Dr. Yat-Yin Au, Dr. Hong Chang, Dr. Prarthana Vadegadde Dakappa, Mr. Joe Shields, Mr. Joe Pady, Ms. Hannah Barnard, and Prof. Geoff Nash, for contributing time, resources, and expertise to various aspects of this work. The authors also thank Dr. Geoff West of Warwick University, for providing cross-sectional TEM imagingPeer reviewe

Single-Step Fabrication of High-Performance Extraordinary Transmission Plasmonic Metasurfaces Employing Ultrafast Lasers

9 pags., 6 figs.Plasmonic metasurfaces based on the extraordinary optical transmission (EOT) effect can be designed to efficiently transmit specific spectral bands from the visible to the far-infrared regimes, offering numerous applications in important technological fields such as compact multispectral imaging, biological and chemical sensing, or color displays. However, due to their subwavelength nature, EOT metasurfaces are nowadays fabricated with nano- and micro-lithographic techniques, requiring many processing steps and carrying out in expensive cleanroom environments. In this work, we propose and experimentally demonstrate a novel, single-step process for the rapid fabrication of high-performance mid- and long-wave infrared EOT metasurfaces employing ultrafast direct laser writing. Microhole arrays composing extraordinary transmission metasurfaces were fabricated over an area of 4 mm2 in timescales of units of minutes, employing single pulse ablation of 40 nm thick Au films on dielectric substrates mounted on a high-precision motorized stage. We show how by carefully characterizing the influence of only three key experimental parameters on the processed micro-morphologies (namely, laser pulse energy, scan velocity, and beam shaping slit), we can have on-demand control of the optical characteristics of the extraordinary transmission effect in terms of transmission wavelength, quality factor, and polarization sensitivity of the resonances. To illustrate this concept, a set of EOT metasurfaces having different performances and operating in different spectral regimes has been successfully designed, fabricated, and tested. Comparison between transmittance measurements and numerical simulations has revealed that all the fabricated devices behave as expected, thus demonstrating the high performance, flexibility, and reliability of the proposed fabrication method. We believe that our findings provide the pillars for mass production of EOT metasurfaces with on-demand optical properties and create new research trends toward single-step laser fabrication of metasurfaces with alternative geometries and/or functionalitiesThis work was financially supported by the Spanish Research Agency (MCIU/AEI/Spain) through project TEC2017- 82464-R and PID2020-112770RB-C21, as well as by the National Research Council of Spain (CSIC) for the intramurales project 201850E05