Bio-Inspired Nanomembranes as Building Blocks for Nanophotonics, Plasmonics and Metamaterials

Nanomembranes are the most widespread building block of life, as they encompass cell and organelle walls. Their synthetic counterparts can be described as freestanding or free-floating structures thinner than 100 nm, down to monatomic/monomolecular thickness and with giant lateral aspect ratios. The structural confinement to quasi-2D sheets causes a multitude of unexpected and often counterintuitive properties. This has resulted in synthetic nanomembranes transiting from a mere scientific curiosity to a position where novel applications are emerging at an ever-accelerating pace. Among wide fields where their use has proven itself most fruitful are nano-optics and nanophotonics. However, the authors are unaware of a review covering the nanomembrane use in these important fields. Here, we present an attempt to survey the state of the art of nanomembranes in nanophotonics, including photonic crystals, plasmonics, metasurfaces, and nanoantennas, with an accent on some advancements that appeared within the last few years. Unlimited by the Nature toolbox, we can utilize a practically infinite number of available materials and methods and reach numerous properties not met in biological membranes. Thus, nanomembranes in nano-optics can be described as real metastructures, exceeding the known materials and opening pathways to a wide variety of novel functionalities

Brochosome-Inspired Metal-Containing Particles as Biomimetic Building Blocks for Nanoplasmonics: Conceptual Generalizations

Recently, biological nanostructures became an important source of inspiration for plasmonics, with many described implementations and proposed applications. Among them are brochosome-inspired plasmonic microstructures—roughly spherical core-shell particles with submicrometer diameters and with indented surfaces. Our intention was to start from the nanoplasmonic point of view and to systematically classify possible alternative forms of brochosome-inspired metal-containing particles producible by the state-of-the-art nanofabrication. A wealth of novel structures arises from this systematization of bioinspired metal-containing nanocomposites. Besides various surface nanoapertures, we consider structures closely related to them in electromagnetic sense like surface nano-protrusions, shell reliefs obtained by nano-sculpting, and various combinations of these. This approach helped us build a new design toolbox for brochosome-inspired structures. Additionally, we used the finite elements method to simulate the optical properties of simple brochosome-inspired structures. We encountered a plethora of advantageous optical traits, including enhanced absorption, antireflective properties, and metamaterial behavior (effective refractive index close to zero or negative). We conclude that the presented approach offers a wealth of traits useful for practical applications. The described research represents our attempt to outline a possible roadmap for further development of bioinspired nanoplasmonic particles and to offer a source of ideas and directions for future research

Super Unit Cells in Aperture-Based Metamaterials

An important class of electromagnetic metamaterials are aperture-based metasurfaces. Examples include extraordinary optical transmission arrays and double fishnets with negative refractive index. We analyze a generalization of such metamaterials where a simple aperture is now replaced by a compound object formed by superposition of two or more primitive objects (e.g., rectangles, circles, and ellipses). Thus obtained "super unit cell" shows far richer behavior than the subobjects that comprise it. We show that nonlocalities introduced by overlapping simple subobjects can be used to produce large deviations of spectral dispersion even for small additive modifications of the basic geometry. Technologically, some super cellsmay be fabricated by simple spatial shifting of the existing photolithographic masks. In our investigation we applied analytical calculations and ab initio finite element modeling to prove the possibility to tailor the dispersion including resonances for plasmonic nanocomposites by adjusting the local geometry and exploiting localized interactions at a subwavelength level. Any desired form could be defined using simple primitive objects, making the situation a geometrical analog of the case of series expansion of a function. Thus an additional degree of tunability of metamaterials is obtained. The obtained designer structures can be applied in different fields like waveguiding and sensing

A Comprehensive Review of Bio-Inspired Optimization Algorithms Including Applications in Microelectronics and Nanophotonics

The application of artificial intelligence in everyday life is becoming all-pervasive and unavoidable. Within that vast field, a special place belongs to biomimetic/bio-inspired algorithms for multiparameter optimization, which find their use in a large number of areas. Novel methods and advances are being published at an accelerated pace. Because of that, in spite of the fact that there are a lot of surveys and reviews in the field, they quickly become dated. Thus, it is of importance to keep pace with the current developments. In this review, we first consider a possible classification of bio-inspired multiparameter optimization methods because papers dedicated to that area are relatively scarce and often contradictory. We proceed by describing in some detail some more prominent approaches, as well as those most recently published. Finally, we consider the use of biomimetic algorithms in two related wide fields, namely microelectronics (including circuit design optimization) and nanophotonics (including inverse design of structures such as photonic crystals, nanoplasmonic configurations and metamaterials). We attempted to keep this broad survey self-contained so it can be of use not only to scholars in the related fields, but also to all those interested in the latest developments in this attractive area

Biomimetic Nanomembranes: An Overview

Nanomembranes are the principal building block of basically all living organisms, and without them life as we know it would not be possible. Yet in spite of their ubiquity, for a long time their artificial counterparts have mostly been overlooked in mainstream microsystem and nanosystem technologies, being a niche topic at best, instead of holding their rightful position as one of the basic structures in such systems. Synthetic biomimetic nanomembranes are essential in a vast number of seemingly disparate fields, including separation science and technology, sensing technology, environmental protection, renewable energy, process industry, life sciences and biomedicine. In this study, we review the possibilities for the synthesis of inorganic, organic and hybrid nanomembranes mimicking and in some way surpassing living structures, consider their main properties of interest, give a short overview of possible pathways for their enhancement through multifunctionalization, and summarize some of their numerous applications reported to date, with a focus on recent findings. It is our aim to stress the role of functionalized synthetic biomimetic nanomembranes within the context of modern nanoscience and nanotechnologies. We hope to highlight the importance of the topic, as well as to stress its great applicability potentials in many facets of human life

Impact of Automation on the Air Traffic Control System Capacity

Neautomatizirani sustavi u kontroli zračnog prometa zahtijevaju veliko radno opterećenje kontrolora u smislu verbalne koordinacije, proračuna parametara leta, subjektivne procjene buduće pozicije zrakoplova, ručnog ispisivanja obrazaca o letu i drugoga. Svrha uvođenja automatiziranih sustava u kontrolu zračnog prometa jest povećanje kapaciteta sustava kontrole zračnog prometa smanjenjem radnog opterećenja kontrolora. Radom je obuhvaćena problematika utjecaja automatizacije na kapacitet sustava kontrole zračnog prometa, a time i na radno opterećenje kontrolora zračnog prometa. Korištenjem znanstvene literature i provođenjem eksperimenta na simulatorskim uređajima koji se upotrebljavaju tijekom osposobljavanja kontrolora zračnog prometa, određen je utjecaj automatiziranih sustava na radno opterećenje kontrolora zračnog prometa. Na temelju toga definiran je model iskorištenja zračnog prostora u obliku ocjene radnog opterećenja i kapaciteta kontrolora zračnog prometa. Analizom rezultata provedenog eksperimenta, simulacija različitih scenarija neautomatiziranog i automatiziranog sustava, identificirane su prednosti i nedostaci automatiziranog sustava u kontroli zračnog prometa u odnosu na promjenu kapaciteta zračnog prostora uz minimalno zadržavanje iste razine učinkovitosti.Non-automated systems in the Air Traffic Control require high air traffic controller workload in terms of conducting the coordination with the aircrew and other controllers, calculation of flight parameters, subjective estimation of the future position of the aircraft, hand writing on the Air Traffic Control strips and other relevant activities. The purpose of the introduction of the automated systems is to increase the Air Traffic Control capacity by achieving the reduction of the controller workload. This dissertation describes the influence of the automation on the Air Traffic Control system as a whole, and by this, it includes the influence of automation on the controllers workload. By using the scientific literature and conducting the experiments on the Air Traffic Control simulators, used for the Air Traffic Controllers simulator training, the analysis of the influence of automated Air Traffic Control systems on the controller’s workload is conducted. Based on the abovementioned statements, the model for the airspace utilization was defined, with the model outputs expressed as quantitative values of the controller’s workload and air traffic control capacity. With the model outputs analysed, it is possible to identify recommendations for the improvement of the Air Traffic Control system. The identification of the recommendations is based on the comparative analysis of the usage of the nonautomated and automated system in air traffic control system environment. With the experiment results analysis and simulations of different exercises in non-automated and automated Air Traffic Control systems, the pros and cons of the usage of the Air Traffic Control automated systems is identified

GUEST EDITORIAL

The field of microelectronics and nanoelectronics devices, circuits and systems including MEMS and NEMS plays a tremendous role in virtually every facet of today’s life. Practically there are no persons whose quality of lives is not being influenced by it. Consequently, there is an enormous increase of the number of novel solutions and applications and an explosive development of related sophisticated production and testing technologies, practical devices and equipment.With the idea to spread knowledge in this key area of engineering and technological knowledge, the Department of Electronics and Communication Engineering, National Institute of Technology Silchar, Assam, India in association with IEEE Electron Devices (ED) NIT Silchar Student Branch Chapter and IEEE Kolkata Section Nanotechnology Council (NTC) Chapter organized the International Virtual Conference on Micro/Nanoelectronics Devices, Circuits and Systems (MNDCS-2021) from 29-31 Jan 2021. The objective was to promote advanced research and developments in the areas of Microelectronics, Nanoelectronics, Semiconductor Devices, VLSI Circuits and Systems through keynotes, invited talks, and oral presentations in the relevant areas

Impact of Automation on the Air Traffic Control System Capacity

Neautomatizirani sustavi u kontroli zračnog prometa zahtijevaju veliko radno opterećenje kontrolora u smislu verbalne koordinacije, proračuna parametara leta, subjektivne procjene buduće pozicije zrakoplova, ručnog ispisivanja obrazaca o letu i drugoga. Svrha uvođenja automatiziranih sustava u kontrolu zračnog prometa jest povećanje kapaciteta sustava kontrole zračnog prometa smanjenjem radnog opterećenja kontrolora. Radom je obuhvaćena problematika utjecaja automatizacije na kapacitet sustava kontrole zračnog prometa, a time i na radno opterećenje kontrolora zračnog prometa. Korištenjem znanstvene literature i provođenjem eksperimenta na simulatorskim uređajima koji se upotrebljavaju tijekom osposobljavanja kontrolora zračnog prometa, određen je utjecaj automatiziranih sustava na radno opterećenje kontrolora zračnog prometa. Na temelju toga definiran je model iskorištenja zračnog prostora u obliku ocjene radnog opterećenja i kapaciteta kontrolora zračnog prometa. Analizom rezultata provedenog eksperimenta, simulacija različitih scenarija neautomatiziranog i automatiziranog sustava, identificirane su prednosti i nedostaci automatiziranog sustava u kontroli zračnog prometa u odnosu na promjenu kapaciteta zračnog prostora uz minimalno zadržavanje iste razine učinkovitosti.Non-automated systems in the Air Traffic Control require high air traffic controller workload in terms of conducting the coordination with the aircrew and other controllers, calculation of flight parameters, subjective estimation of the future position of the aircraft, hand writing on the Air Traffic Control strips and other relevant activities. The purpose of the introduction of the automated systems is to increase the Air Traffic Control capacity by achieving the reduction of the controller workload. This dissertation describes the influence of the automation on the Air Traffic Control system as a whole, and by this, it includes the influence of automation on the controllers workload. By using the scientific literature and conducting the experiments on the Air Traffic Control simulators, used for the Air Traffic Controllers simulator training, the analysis of the influence of automated Air Traffic Control systems on the controller’s workload is conducted. Based on the abovementioned statements, the model for the airspace utilization was defined, with the model outputs expressed as quantitative values of the controller’s workload and air traffic control capacity. With the model outputs analysed, it is possible to identify recommendations for the improvement of the Air Traffic Control system. The identification of the recommendations is based on the comparative analysis of the usage of the nonautomated and automated system in air traffic control system environment. With the experiment results analysis and simulations of different exercises in non-automated and automated Air Traffic Control systems, the pros and cons of the usage of the Air Traffic Control automated systems is identified

Investigation of Nonlinear Piezoelectric Energy Harvester for Low-Frequency and Wideband Applications

This paper proposes a monostable nonlinear Piezoelectric Energy Harvester (PEH). The harvester is based on an unconventional exsect-tapered fixed-guided spring design, which introduces nonlinearity into the system due to the bending and stretching of the spring. The physical–mathematical model and finite element simulations were performed to analyze the effects of the stretching-induced nonlinearity on the performance of the energy harvester. The proposed exsect-tapered nonlinear PEH shows a bandwidth and power enhancement of 15.38 and 44.4%, respectively, compared to conventional rectangular nonlinear PEHs. It shows a bandwidth and power enhancement of 11.11 and 26.83%, respectively, compared to a simple, linearly tapered and nonlinear PEH. The exsect-tapered nonlinear PEH improves the power output and operational bandwidth for harvesting low-frequency ambient vibrations

MEMS RESONATOR MASS LOADING NOISE MODEL: THE CASE OF BIMODAL ADSORBING SURFACE AND FINITE ADSORBATE AMOUNT

Modeling of adsorption and desorption in microelectromechanical systems (MEMS) generally is crucial for their optimization and control, whether it is necessary to decrease the adsorption-desorption influence (thus ensuring stable operation of ultra-precise micro and nanoresonators) or to increase it (and enhancing in this manner the sensitivity of chemical and biological resonant sensors). In this work we derive and use analytical mathematical expressions to model stochastic fluctuations of the mass adsorbed on the MEMS resonator (mass loading noise). We consider the case where the resonator surface incorporates two different types of binding sites and where non-negligible depletion of the adsorbate occurs in a closed resonator chamber. We arrive at a novel expression for the power spectral density of mass loading noise in resonators and prove the necessity of its application in cases when resonators are exposed to low adsorbate concentrations. We use the novel approach presented here to calculate the resonator performance. In this way we ensure optimization of these MEMS devices and consequentially abatement of adsorption-desorption noise-caused degradation of their operation, both in the case of micro/nanoresonators and resonant sensors. This work is intended for a general use in the design, development and optimization of different MEMS systems based on mechanical resonators, ranging from the RF components to chemical and biological sensors