Nonreciprocal and Topological Plasmonics

Total Page:16

File Type:pdf, Size:1020Kb

Nonreciprocal and Topological Plasmonics hv photonics Review Nonreciprocal and Topological Plasmonics Kunal Shastri , Mohamed Ismail Abdelrahman and Francesco Monticone * School of Electrical and Computer Engineering, Cornell University, Ithaca, NY 14853, USA; [email protected] (K.S.); [email protected] (M.I.A.) * Correspondence: [email protected] Abstract: Metals, semiconductors, metamaterials, and various two-dimensional materials with plasmonic dispersion exhibit numerous exotic physical effects in the presence of an external bias, for example an external static magnetic field or electric current. These physical phenomena range from Faraday rotation of light propagating in the bulk to strong confinement and directionality of guided modes on the surface and are a consequence of the breaking of Lorentz reciprocity in these systems. The recent introduction of relevant concepts of topological physics, translated from condensed-matter systems to photonics, has not only given a new perspective on some of these topics by relating certain bulk properties of plasmonic media to the surface phenomena, but has also led to the discovery of new regimes of truly unidirectional, backscattering-immune, surface-wave propagation. In this article, we briefly review the concepts of nonreciprocity and topology and describe their manifestation in plasmonic materials. Furthermore, we use these concepts to classify and discuss the different classes of guided surface modes existing on the interfaces of various plasmonic systems. Keywords: plasmonics; nanophotonics; nonreciprocity; topological physics; surface waves 1. Introduction Various metals, gas plasmas, highly doped semiconductors, and metamaterials that Citation: Shastri, K.; Abdelrahman, can be modelled as weakly interacting gases of charged particles do not support light M.I.; Monticone, F. Nonreciprocal and propagation within their bulk at frequencies lower than their plasma frequency, a direct Topological Plasmonics. Photonics consequence of their negative permittivity in this regime. However, at the interface be- 2021, 8, 133. https://doi.org/ tween such a plasmonic material and a dielectric, collective charge oscillations coupled to 10.3390/photonics8040133 electromagnetic fields result in surface-plasmon-polariton modes that are strongly confined to the two-dimensional (2D) interface and evanescently decay in the bulk. Analogous to Received: 22 February 2021 the everyday experience of seeing surface gravity waves propagating in all directions on Accepted: 12 April 2021 the surface of a water body that is perturbed by a dropped pebble, these surface plasmon- Published: 20 April 2021 polaritons do not have any preferential direction when propagating on a homogenous isotropic 2D interface. Conversely, if the plasmonic material is magnetized, the resulting Publisher’s Note: MDPI stays neutral Lorentz force affects the motion of the charged particles and breaks this isotropy and sym- with regard to jurisdictional claims in metry, modifying the dispersion of bulk and surface modes. Notably, a magnetic bias opens published maps and institutional affil- iations. a frequency window where backward-propagating surface waves are prohibited [1–6]. These unidirectional surface plasmon-polariton modes on magnetized plasma-dielectric interfaces, known as surface magneto-plasmons, were first discovered several decades ago, and are just one example of the host of unidirectional surface modes existing on com- plex (anisotropic, chiral, nonreciprocal) plasmonic materials. Such plasmonic platforms Copyright: © 2021 by the authors. combine the advantages of subwavelength light confinement and enhancement offered Licensee MDPI, Basel, Switzerland. by plasmonics with the backscattering-immune transport characteristics of unidirectional This article is an open access article waves, and they are being increasingly investigated for novel or enhanced functionalities, distributed under the terms and conditions of the Creative Commons such as compact Faraday rotation, isolation, and circulation [7–10] and extreme light-matter Attribution (CC BY) license (https:// interactions, field enhancement, and giant nonlinear effects [11–14], to name a few. In this creativecommons.org/licenses/by/ article, we review the rich physics of unidirectional surface modes on complex plasmonic 4.0/). Photonics 2021, 8, 133. https://doi.org/10.3390/photonics8040133 https://www.mdpi.com/journal/photonics Photonics 2021, 8, 133 2 of 22 Photonics 2021, 8, 133 2 of 21 a few. In this article, we review the rich physics of unidirectional surface modes on com- plex plasmonic materials, relating them to the properties of the bulk modes, and distin- materials,guishing relatingbetween them various to the classes properties of surface of the waves bulk modes,based on and the distinguishing concepts of reciprocity between variousand topology. classes of surface waves based on the concepts of reciprocity and topology. BeforeBefore studying studying these these different different types types of surfaceof surface waves waves in detail, in detail, let us let briefly us briefly introduce intro- someduce general some general concepts concepts related related to the principleto the principle of reciprocity of reciprocity and how and ideas how of ideas topological of topo- wave-physics enter the problem. Reciprocity in electromagnetics is the general principle logical wave-physics enter the problem. Reciprocity in electromagnetics is the general that the ratio of the field detected by a detector to the field emitted by a source are the principle that the ratio of the field detected by a detector to the field emitted by a source same if the source and detector are interchanged [15–17]. For reciprocal media, such as a are the same if the source and detector are interchanged [15–17]. For reciprocal media, simple non-biased plasmonic material, the dispersion of any eigenmode (including surface such as a simple non-biased plasmonic material, the dispersion of any eigenmode (includ- modes) does not depend on the sign of the wavevector k, w(k) = w(−k), as shown in ing surface modes) does not depend on the sign of the wavevector k , ωω()kk=− ( ), as Figure1a,b. This strict symmetry condition rules out the possibility of realizing truly shown in Figure 1a,b. This strict symmetry condition rules out the possibility of realizing unidirectional surface waves on reciprocal media, irrespective of any consideration related totruly the topologicalunidirectional nature surface of the wa materialves on reciprocal (more on media, this below). irrespective We stress of any that, consideration although lossyrelated plasmonic to the topological materials breaknature time-reversal of the material symmetry (more on at this the below). macroscopic We stress level, that, they alt- cannothough overcome lossy plasmonic this limitation, materials since break breaking time-reversal time-reversal symmetry symmetry at the macroscopic is not equivalent level, tothey breaking cannot reciprocity overcome (the this two limitation, concepts since are equivalentbreaking time-reversal only for lossless symmetry media), is as not further equiv- elucidatedalent to breaking in [15]. reciprocity Therefore, (the the two only concepts way to realizeare equivalent an asymmetric only for surface-plasmon-lossless media), as polaritonfurther elucidated dispersion in is [15]. to break Therefore, reciprocity, the only as shown way to in realize Figure an1c,d, asymmetric which is achieved surface-plas- by biasingmon-polariton the system dispersion with an externalis to break physical reciprocity, quantity as that shown is odd in upon Figure time 1c,d, reversal, which for is exampleachieved an by external biasing magnetic the system field with or aan drift external current physical [15]. quantity that is odd upon time reversal, for example an external magnetic field or a drift current [15]. Figure 1. Reciprocal/nonreciprocal and topological/nontopological surface plasmon-polariton modes. (a,b) Model disper- Figure 1. Reciprocal/nonreciprocal and topological/nontopological surface plasmon-polariton modes. (a,b) Model dis- sion diagrams of reciprocal surface plasmon-polaritons that can be classified as topologically trivial and non-trivial, re- persion diagrams of reciprocal surface plasmon-polaritons that can be classified as topologically trivial and non-trivial, spectively. The equifrequency contours of the dispersion surfaces for these modes at two different frequency values are respectively.plotted on the The right equifrequency insets. It can contours be seen of that the dispersionthe dispersion surfaces curves for theseare symmetr modesic at in two momentum different frequency space for valuesboth cases, are plottedωω()kk=− on ( the ) right, but contrary insets. It to can (a), be the seen topologically that the dispersion protected curves mode arein ( symmetricb) does not inbackscatter momentum (within space afor certain both angular cases, w(k) = w(−k), but contrary to (a), the topologically protected mode in (b) does not backscatter (within a certain angular range) for defects that preserve the ky component of momentum, as indicated by the dashed blue line. Blue arrows denote range) for defects that preserve the k component of momentum, as indicated by the dashed blue line. Blue arrows denote the the group velocity vector for a certainy value of momentum. (c,d) Examples of non-reciprocal surface plasmon-polariton groupmodes. velocity The equifrequency vector for a certain contours value are of strongly momentum. asymmetric (c,d)
Recommended publications
  • Quantum Optics with Giant Atoms – the First Five Years
    Quantum optics with giant atoms – the first five years Anton Frisk Kockum Abstract In quantum optics, it is common to assume that atoms can be approximated as point-like compared to the wavelength of the light they interact with. However, recent advances in experiments with artificial atoms built from superconducting circuits have shown that this assumption can be violated. Instead, these artificial atoms can couple to an electromagnetic field at multiple points, which are spaced wavelength distances apart. In this chapter, we present a survey of such systems, which we call giant atoms. The main novelty of giant atoms is that the multiple coupling points give rise to interference effects that are not present in quantum optics with ordinary, small atoms. We discuss both theoretical and experimental results for single and multiple giant atoms, and show how the interference effects can be used for interesting applications. We also give an outlook for this emerging field of quantum optics. Key words: Quantum optics, Giant atoms, Waveguide QED, Relaxation rate, Lamb shift, Superconducting qubits, Surface acoustic waves, Cold atoms 1 Introduction Natural atoms are so small (radius r ≈ 10−10 m) that they can be considered point- like when they interact with light at optical frequencies (wavelength λ ≈ 10−6 − 10−7 m)[1]. If the atoms are excited to high Rydberg states, they can reach larger sizes (r ≈ 10−8 − 10−7 m), but quantum-optics experiments with such atoms have them interact with microwave radiation, which has much longer wavelength (λ ≈ arXiv:1912.13012v1 [quant-ph] 30 Dec 2019 10−2 −10−1 m)[2].
    [Show full text]
  • Merging Photonics and Artificial Intelligence at the Nanoscale
    Intelligent Nanophotonics: Merging Photonics and Artificial Intelligence at the Nanoscale Kan Yao1,2, Rohit Unni2 and Yuebing Zheng1,2,* 1Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA 2Texas Materials Institute, The University of Texas at Austin, Austin, Texas 78712, USA *Corresponding author: [email protected] Abstract: Nanophotonics has been an active research field over the past two decades, triggered by the rising interests in exploring new physics and technologies with light at the nanoscale. As the demands of performance and integration level keep increasing, the design and optimization of nanophotonic devices become computationally expensive and time-inefficient. Advanced computational methods and artificial intelligence, especially its subfield of machine learning, have led to revolutionary development in many applications, such as web searches, computer vision, and speech/image recognition. The complex models and algorithms help to exploit the enormous parameter space in a highly efficient way. In this review, we summarize the recent advances on the emerging field where nanophotonics and machine learning blend. We provide an overview of different computational methods, with the focus on deep learning, for the nanophotonic inverse design. The implementation of deep neural networks with photonic platforms is also discussed. This review aims at sketching an illustration of the nanophotonic design with machine learning and giving a perspective on the future tasks. Keywords: deep learning; (nano)photonic neural networks; inverse design; optimization. 1. Introduction Nanophotonics studies light and its interactions with matters at the nanoscale [1]. Over the past decades, it has received rapidly growing interest and become an active research field that involves both fundamental studies and numerous applications [2,3].
    [Show full text]
  • Transverse-Mode Coupling Effects in Scanning Cavity Microscopy
    PAPER • OPEN ACCESS Transverse-mode coupling effects in scanning cavity microscopy To cite this article: Julia Benedikter et al 2019 New J. Phys. 21 103029 View the article online for updates and enhancements. This content was downloaded from IP address 130.183.90.175 on 07/01/2020 at 15:23 New J. Phys. 21 (2019) 103029 https://doi.org/10.1088/1367-2630/ab49b4 PAPER Transverse-mode coupling effects in scanning cavity microscopy OPEN ACCESS Julia Benedikter1,2, Thea Moosmayer2, Matthias Mader1,3, Thomas Hümmer1,3 and David Hunger2 RECEIVED 1 Fakultät für Physik, Ludwig-Maximilians-Universität, Schellingstraße4, D-80799München, Germany 5 August 2019 2 Karlsruher Institut für Technologie, Physikalisches Institut, Wolfgang-Gaede-Str. 1, D-76131 Karlsruhe, Germany REVISED 3 Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Str.1, D-85748Garching, Germany 11 September 2019 ACCEPTED FOR PUBLICATION E-mail: [email protected] 1 October 2019 Keywords: optical microcavities, Fabry–Perot resonators, mode mixing, fiber cavity PUBLISHED 15 October 2019 Supplementary material for this article is available online Original content from this work may be used under Abstract the terms of the Creative Commons Attribution 3.0 Tunable open-access Fabry–Pérot microcavities enable the combination of cavity enhancement with licence. high resolution imaging. To assess the limits of this technique originating from background variations, Any further distribution of this work must maintain we perform high-finesse scanning cavity microscopy of pristine planar mirrors. We observe spatially attribution to the author(s) and the title of localized features of strong cavity transmission reduction for certain cavity mode orders, and periodic the work, journal citation background patterns with high spatial frequency.
    [Show full text]
  • Up-And-Coming Physical Concepts of Wireless Power Transfer
    Up-And-Coming Physical Concepts of Wireless Power Transfer Mingzhao Song1,2 *, Prasad Jayathurathnage3, Esmaeel Zanganeh1, Mariia Krasikova1, Pavel Smirnov1, Pavel Belov1, Polina Kapitanova1, Constantin Simovski1,3, Sergei Tretyakov3, and Alex Krasnok4 * 1School of Physics and Engineering, ITMO University, 197101, Saint Petersburg, Russia 2College of Information and Communication Engineering, Harbin Engineering University, 150001 Harbin, China 3Department of Electronics and Nanoengineering, Aalto University, P.O. Box 15500, FI-00076 Aalto, Finland 4Photonics Initiative, Advanced Science Research Center, City University of New York, NY 10031, USA *e-mail: [email protected], [email protected] Abstract The rapid development of chargeable devices has caused a great deal of interest in efficient and stable wireless power transfer (WPT) solutions. Most conventional WPT technologies exploit outdated electromagnetic field control methods proposed in the 20th century, wherein some essential parameters are sacrificed in favour of the other ones (efficiency vs. stability), making available WPT systems far from the optimal ones. Over the last few years, the development of novel approaches to electromagnetic field manipulation has enabled many up-and-coming technologies holding great promises for advanced WPT. Examples include coherent perfect absorption, exceptional points in non-Hermitian systems, non-radiating states and anapoles, advanced artificial materials and metastructures. This work overviews the recent achievements in novel physical effects and materials for advanced WPT. We provide a consistent analysis of existing technologies, their pros and cons, and attempt to envision possible perspectives. 1 Wireless power transfer (WPT), i.e., the transmission of electromagnetic energy without physical connectors such as wires or waveguides, is a rapidly developing technology increasingly being introduced into modern life, motivated by the exponential growth in demand for fast and efficient wireless charging of battery-powered devices.
    [Show full text]
  • Polarization (Waves)
    Polarization (waves) Polarization (also polarisation) is a property applying to transverse waves that specifies the geometrical orientation of the oscillations.[1][2][3][4][5] In a transverse wave, the direction of the oscillation is perpendicular to the direction of motion of the wave.[4] A simple example of a polarized transverse wave is vibrations traveling along a taut string (see image); for example, in a musical instrument like a guitar string. Depending on how the string is plucked, the vibrations can be in a vertical direction, horizontal direction, or at any angle perpendicular to the string. In contrast, in longitudinal waves, such as sound waves in a liquid or gas, the displacement of the particles in the oscillation is always in the direction of propagation, so these waves do not exhibit polarization. Transverse waves that exhibit polarization include electromagnetic [6] waves such as light and radio waves, gravitational waves, and transverse Circular polarization on rubber sound waves (shear waves) in solids. thread, converted to linear polarization An electromagnetic wave such as light consists of a coupled oscillating electric field and magnetic field which are always perpendicular; by convention, the "polarization" of electromagnetic waves refers to the direction of the electric field. In linear polarization, the fields oscillate in a single direction. In circular or elliptical polarization, the fields rotate at a constant rate in a plane as the wave travels. The rotation can have two possible directions; if the fields rotate in a right hand sense with respect to the direction of wave travel, it is called right circular polarization, while if the fields rotate in a left hand sense, it is called left circular polarization.
    [Show full text]
  • Graphene Plasmonics: Physics and Potential Applications
    Graphene plasmonics: Physics and potential applications Shenyang Huang1,2, Chaoyu Song1,2, Guowei Zhang1,2, and Hugen Yan1,2* 1Department of Physics, State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), Fudan University, Shanghai 200433, China 2Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China *Email: [email protected] Abstract Plasmon in graphene possesses many unique properties. It originates from the collective motion of massless Dirac fermions and the carrier density dependence is distinctively different from conventional plasmons. In addition, graphene plasmon is highly tunable and shows strong energy confinement capability. Most intriguing, as an atom-thin layer, graphene and its plasmon are very sensitive to the immediate environment. Graphene plasmons strongly couple to polar phonons of the substrate, molecular vibrations of the adsorbates, and lattice vibrations of other atomically thin layers. In this review paper, we'll present the most important advances in grapene plasmonics field. The topics include terahertz plasmons, mid-infrared plasmons, plasmon-phonon interactions and potential applications. Graphene plasmonics opens an avenue for reconfigurable metamaterials and metasurfaces. It's an exciting and promising new subject in the nanophotonics and plasmonics research field. 1 Introduction Graphene is a fascinating electronic and optical material and the study for graphene started with its magneto-transport measurements and an anomalous Berry phase[1, 2]. Optical properties of graphene attracted more and more attention later on. Many exciting developments have been achieved, such as universal optical conductivity[3], tunable optical absorption[4, 5] and strong terahertz response[6]. Most importantly, as an interdisciplinary topic, plasmon in graphene has been the major focus of graphene photonics in recent years.
    [Show full text]
  • DNA Nanotechnology Meets Nanophotonics
    DNA nanotechnology meets nanophotonics Na Liu 2nd Physics Institute, University of Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany Email: [email protected] Key words: DNA nanotechnology, nanophotonics, DNA origami, light matter interactions Call-out sentence: It will be very constructive, if more research funds become available to support young researchers with bold ideas and meanwhile allow for failures and contingent outcomes. The first time I heard the two terms ‘DNA nanotechnology’ and ‘nanophotonics’ mentioned together was from Paul Alivisatos, who delivered the Max Planck Lecture in Stuttgart, Germany, on a hot summer day in 2008. In his lecture, Paul showed how a plasmon ruler containing two metallic nanoparticles linked by a DNA strand could be used to monitor nanoscale distance changes and even the kinetics of single DNA hybridization events in real time, readily correlating nanoscale motion with optical feedback.1 Until this day, I still vividly remember my astonishment by the power and beauty of these two nanosciences, when rigorously combined together. In the past decades, DNA has been intensely studied and exploited in different research areas of nanoscience and nanotechnology. At first glance, DNA-based nanophotonics seems to deviate quite far from the original goal of Nadrian Seeman, the founder of DNA nanotechnology, who hoped to organize biological entities using DNA in high-resolution crystals. As a matter of fact, DNA-based nanophotonics does closely follow his central spirit. That is, apart from being a genetic material for inheritance, DNA is also an ideal material for building molecular devices.
    [Show full text]
  • Inverse Design for Silicon Photonics: from Iterative Optimization Algorithms to Deep Neural Networks
    applied sciences Review Inverse Design for Silicon Photonics: From Iterative Optimization Algorithms to Deep Neural Networks Simei Mao 1,2, Lirong Cheng 1,2 , Caiyue Zhao 1,2, Faisal Nadeem Khan 2, Qian Li 3 and H. Y. Fu 1,2,* 1 Tsinghua-Berkeley Shenzhen Institute, Tsinghua University, Shenzhen 518055, China; [email protected] (S.M.); [email protected] (L.C.); [email protected] (C.Z.) 2 Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China; [email protected] 3 School of Electronic and Computer Engineering, Peking University, Shenzhen 518055, China; [email protected] * Correspondence: [email protected]; Tel.: +86-755-3688-1498 Abstract: Silicon photonics is a low-cost and versatile platform for various applications. For design of silicon photonic devices, the light-material interaction within its complex subwavelength geometry is difficult to investigate analytically and therefore numerical simulations are majorly adopted. To make the design process more time-efficient and to improve the device performance to its physical limits, various methods have been proposed over the past few years to manipulate the geometries of silicon platform for specific applications. In this review paper, we summarize the design methodologies for silicon photonics including iterative optimization algorithms and deep neural networks. In case of iterative optimization methods, we discuss them in different scenarios in the sequence of increased degrees of freedom: empirical structure, QR-code like structure and irregular structure. We also review inverse design approaches assisted by deep neural networks, which generate multiple devices Citation: Mao, S.; Cheng, L.; Zhao, with similar structure much faster than iterative optimization methods and are thus suitable in C.; Khan, F.N.; Li, Q.; Fu, H.Y.
    [Show full text]
  • Wirelessly-Powered Cage Designs for Supporting Long-Term Experiments on Small Freely Behaving Animals in a Large Experimental Arena
    electronics Review Wirelessly-Powered Cage Designs for Supporting Long-Term Experiments on Small Freely Behaving Animals in a Large Experimental Arena Byunghun Lee 1 and Yaoyao Jia 2,* 1 Department of Electrical Engineering, Incheon National University, Incheon 22012, Korea; [email protected] 2 Department of Electrical and Computer Engineering, North Carolina State University, 890 Oval Dr, Raleigh, NC 27606, USA * Correspondence: [email protected]; Tel.: +1-919-515-7350 Received: 22 October 2020; Accepted: 18 November 2020; Published: 25 November 2020 Abstract: In modern implantable medical devices (IMDs), wireless power transmission (WPT) between inside and outside of the animal body is essential to power the IMD. Unlike conventional WPT, which transmits the wireless power only between fixed Tx and Rx coils, the wirelessly-powered cage system can wirelessly power the IMD implanted in a small animal subject while the animal freely moves inside the cage during the experiment. A few wirelessly-powered cage systems have been developed to either directly power the IMD or recharge batteries during the experiment. Since these systems adapted different power carrier frequencies, coil configurations, subject tracking techniques, and wireless powered area, it is important for designers to select suitable wirelessly-powered cage designs, considering the practical limitations in wirelessly powering the IMD, such as power transfer efficiency (PTE), power delivered to load (PDL), closed-loop power control (CLPC), scalability, spatial/angular misalignment, near-field data telemetry, and safety issues against various perturbations during the longitudinal animal experiment. In this article, we review the trend of state-of-the-art wirelessly-powered cage designs and practical considerations of relevant technologies for various IMD applications.
    [Show full text]
  • NANOPHOTONICS a FORWARD LOOK NANOPHOTONICS Association a FORWARD LOOK
    association NANOPHOTONICS A FORWARD LOOK NANOPHOTONICS association A FORWARD LOOK Report Editors Gonçal Badenes, ICFO Stewe Bekk, ICFO Martin Goodwin, 2020 Insights DESIGN Sergio Simón Petreñas D.L. B-29170-2012 (Printed version) B-29171-2012 (Electronic version) © 2012 NEA. The text of this publication may be reproduced provided the source is acknowledged. Reproduction for commercial use without prior permission is prohibited. PICTURES © reserved by original copyright holder. Reproduction of the artistic material contained therein is prohibited The Nanophotonics Europe Association is partially funded by the Spanish Ministry of Economy and Competitiveness through grant ACI-2009-1013 NANOPHOTONICS association A FORWARD LOOK About this Report This document is the report of the Nanophotonics Europe Association workshop held at King's College, London (UK) in July 2012. The purpose was to define a strategy for advancing research and development of nanophotonics. The views, ideas, conclusions and recommendations presented in this report are those of the workshop participants. Nanophotonics Europe Association The Nanophotonics Europe Association (NEA) is a not-for-profit organisation created to promote and advance European science and technology in the emerging area of nanophotonics. The goals of the association are fourfold: 1. To promote research in nanophotonics by coordinating the efforts of the various players involved, and, in particular, by encouraging collaboration between academic institution and industry. 2. To create a common interest group that represents member’s interests with national and transnational scientific government funding agencies, technology platforms, professional associations and the general public. 3. To integrate the resources and strategies of its members. 4. To facilitate the exchange of information, ideas and data.
    [Show full text]
  • 7 Plasmonics
    7 Plasmonics Highlights of this chapter: In this chapter we introduce the concept of surface plasmon polaritons (SPP). We discuss various types of SPP and explain excitation methods. Finally, di®erent recent research topics and applications related to SPP are introduced. 7.1 Introduction Long before scientists have started to investigate the optical properties of metal nanostructures, they have been used by artists to generate brilliant colors in glass artefacts and artwork, where the inclusion of gold nanoparticles of di®erent size into the glass creates a multitude of colors. Famous examples are the Lycurgus cup (Roman empire, 4th century AD), which has a green color when observing in reflecting light, while it shines in red in transmitting light conditions, and church window glasses. Figure 172: Left: Lycurgus cup, right: color windows made by Marc Chagall, St. Stephans Church in Mainz Today, the electromagnetic properties of metal{dielectric interfaces undergo a steadily increasing interest in science, dating back in the works of Gustav Mie (1908) and Rufus Ritchie (1957) on small metal particles and flat surfaces. This is further moti- vated by the development of improved nano-fabrication techniques, such as electron beam lithographie or ion beam milling, and by modern characterization techniques, such as near ¯eld microscopy. Todays applications of surface plasmonics include the utilization of metal nanostructures used as nano-antennas for optical probes in biology and chemistry, the implementation of sub-wavelength waveguides, or the development of e±cient solar cells. 208 7.2 Electro-magnetics in metals and on metal surfaces 7.2.1 Basics The interaction of metals with electro-magnetic ¯elds can be completely described within the frame of classical Maxwell equations: r ¢ D = ½ (316) r ¢ B = 0 (317) r £ E = ¡@B=@t (318) r £ H = J + @D=@t; (319) which connects the macroscopic ¯elds (dielectric displacement D, electric ¯eld E, magnetic ¯eld H and magnetic induction B) with an external charge density ½ and current density J.
    [Show full text]
  • Towards Deep Integration of Electronics and Photonics
    applied sciences Review Towards Deep Integration of Electronics and Photonics Ivan A. Pshenichnyuk 1,* , Sergey S. Kosolobov 1 and Vladimir P. Drachev 1,2,* 1 Skolkovo Institute of Science and Technology, Center for Photonics and Quantum Materials, Nobelya 3, 121205 Moscow, Russia; [email protected] 2 Department of Physics, University of North Texas,1155 Union Circle, Denton, TX 76203, USA * Correspondence: [email protected] (I.A.P.); [email protected] (V.P.D.) Received: 15 September 2019; Accepted: 5 November 2019; Published: 12 November 2019 Abstract: A combination of computational power provided by modern MOSFET-based devices with light assisted wideband communication at the nanoscale can bring electronic technologies to the next level. Obvious obstacles include a size mismatch between electronic and photonic components as well as a weak light–matter interaction typical for existing devices. Polariton modes can be used to overcome these difficulties at the fundamental level. Here, we review applications of such modes, related to the design and fabrication of electro–optical circuits. The emphasis is made on surface plasmon-polaritons which have already demonstrated their value in many fields of technology. Other possible quasiparticles as well as their hybridization with plasmons are discussed. A quasiparticle-based paradigm in electronics, developed at the microscopic level, can be used in future molecular electronics and quantum computing. Keywords: plasmon; light-matter interaction; photonics; nano-electronics; quasiparticle 1. Introduction Further achievements in electronics and photonics imply their better integration. Usage of photons at the level of circuits and single chips has a huge potential to improve modern intelligent systems [1].
    [Show full text]