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Nanosensor Laboratory
Published in Vinod Kumar Khanna, Nanosensors, 2021
Two main methods for communication are envisioned at the nanoscale: (i) molecular communication, defined as the transmission and reception of information encoded in molecules; and (ii) nanoelectromagnetic communication, dealing with the transmission and reception of electromagnetic radiation from components utilizing novel nanomaterials. Electromagnetic communication among nanosensors will be aided by the development of nanoantennas and the corresponding electromagnetic transceiver. To seek the nanoantenna goal (Hagerty et al. 2004), the following approaches are likely: (i) more accurate models for nanoantennas based on nanotubes and nanoribbons need to be formulated, by providing their specific bands of operation, radiation bandwidth, and radiation efficiency. All these parameters will determine the communication capabilities of nanosensor devices; (ii) novel nanoantenna designs and radiating nanostructures must be put forward by exploiting the properties of nanomaterials and new manufacturing techniques; and (iii) a new antenna theory must be framed by considering the quantum effects observed at the nanoscale.
The FDTD Method: Essences, Evolutions, and Applications to Nano-Optics and Quantum Physics
Published in Sarhan M. Musa, Computational Nanotechnology Using Finite Difference Time Domain, 2017
Xiaoyan Y.Z. Xiong, Wei E.I. Sha
Nanoantennas [72, 75, 98–103] play a fundamental role in nanotechnology due to their capabilities to confine and enhance the light through converting the localized to propagating electromagnetic fields, and vice versa. The nanoantenna is a direct analogue and extended technology of the radio wave and microwave antenna. But the nanoantenna possesses lots of individual and novel features mainly owing to the existence of the electron gas oscillations in metals. The behavior of strongly coupled plasmas and the capability of manipulating light on the nanometer scale make nanoantenna particularly useful in microscopy and spectroscopy [104], fluorescence enhancement [101], surface-enhanced Raman spectroscopy [105], and photovoltaics [106,107]. The above applications mainly rely on the characteristics of nanoantennas, such as the resonance frequency, bandwidth, directivity, far-field radiation pattern, near-field distribution, and local density of states. Here, we use the FDTD method to simulate a typical dipole nanoantenna with the schematic pattern shown in Figure 2.8. The relative permittivity of Al2O3 is 3.065 and the excitation source is a plane wave polarized along the arm direction of the antenna. Figure 2.9 demonstrates that the resonance frequency of the antenna can be tunable in a wide range by changing the arm length of the antenna. The absorption cross section can be defined by
Fluorescence Spectroscopy Enhancement on Photonic Nanoantennas
Published in Marc Lamy de la Chapelle, Nordin Felidj, Plasmonics in Chemistry and Biology, 2019
To overcome the diffraction limit, nanoantenna designs take advantage of sharp curvature radii, nanoscale gaps and plasmonic resonances, using metal nanostructures (Novotny, 2011). A large number of approaches have been investigated over the last decade in order to enhance the fluorescence emission of single molecules and quantum dots (Holzmeister, 2013; Punj, 2014; Lakowicz, 2009). While classical top-down lithography like electron-beam lithography or focused ion beam milling remains the workhorse for fabricating the nanoantennas, alternative bottom-up strategies using nanoparticle assembly have recently seen much development driven by the seek for a simpler and higher throughput nanofabrication approach.
Infrared rectification based on electron field emission in nanoantennas for thermal energy harvesting
Published in Journal of Modern Optics, 2020
A. Chekini, M. Neshat, S. Sheikhaei
Another group of researchers keep a second viewpoint on energy harvesting from light sources to overcome the above-mentioned challenges. Applying the wave theory of light is the main idea behind this approach. In particular, for energy harvesting in visible and infrared wavelengths, the antenna theory has been applied to adapt the techniques used for capturing radio frequencies. Bailey in 1972 initially presented the concept of solar energy harvesting by introducing nanoantennas (8). Next, other researchers developed nanoantenna-based devices for solar energy harvesting (9–11). Operation principle of these structures is based on a fact that when an electromagnetic wave is incident on a nanoantenna surface, a time-varying current is induced in the nanoantenna (12–14). Such current oscillates at the frequency of the incident wave that should be rectified to provide usable electric power. A complete review of the energy harvesting from Earth’s thermal infrared emission is presented in (15). In particular, different features of THz and IR antennas such as system design considerations, physical properties and antenna parameters, and the antenna coupling to a rectifying diode with emphasis on the recent progresses have been reviewed.
State of the Art of Nanoantenna Designs in Infrared and Visible Regions: An Application-Oriented Review
Published in IETE Technical Review, 2022
Priya Ranjan Meher, Abhiram Reddy Cholleti, Sanjeev Kumar Mishra
The field of nanoantenna in energy harvesting [17–41] with a significant interest provides an alternate solution to current technology by contributing clean energy to the environment. Solar cells are used for energy harvesting which works only in the visible region and fails in collecting the energy from the infrared region. To mitigate this problem, the evolution of nanoantenna became a perfect solution in utilizing energy. These nanoantennas were designed to work in the infrared and visible regime, hence fabricating them on a large scale will be an add-on to the power grid. In addition, the authors have designed the proposed multi-layered nanoantenna that provides better efficiency and wider bandwidth required for energy harvesting applications.