Broadband Electromagnetic Cloaking with Smart Metamaterials
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Review 330 Fall 2019 SFRA
SFRA RREVIEWS, ARTICLES,e ANDview NEWS FROM THE SFRA SINCE 1971 330 Fall 2019 FEATURING Area X: Five Years Later PB • SFRA Review 330 • Fall 2019 Proceedings of the SFRASFRA 2019 Review 330Conference • Fall 2019 • 1 330 THE OPEN ACCESS JOURNAL OF THE Fall 2019 SFRA MASTHEAD ReSCIENCE FICTIONview RESEARCH ASSOCIATION SENIOR EDITORS ISSN 2641-2837 EDITOR SFRA Review is an open access journal published four times a year by Sean Guynes Michigan State University the Science Fiction Research Association (SFRA) since 1971. SFRA [email protected] Review publishes scholarly articles and reviews. The Review is devoted to surveying the contemporary field of SF scholarship, fiction, and MANAGING EDITOR media as it develops. Ian Campbell Georgia State University [email protected] Submissions ASSOCIATE EDITOR SFRA Review accepts original scholarly articles; interviews; Virginia Conn review essays; individual reviews of recent scholarship, fiction, Rutgers University and media germane to SF studies. [email protected] ASSOCIATE EDITOR All submissions should be prepared in MLA 8th ed. style and Amandine Faucheux submitted to the appropriate editor for consideration. Accepted University of Louisiana at Lafayette pieces are published at the discretion of the editors under the [email protected] author's copyright and made available open access via a CC-BY- NC-ND 4.0 license. REVIEWS EDITORS NONFICTION EDITOR SFRA Review does not accept unsolicited reviews. If you would like Dominick Grace to write a review essay or review, please contact the appropriate Brescia University College [email protected] review editor. For all other publication types—including special issues and symposia—contact the editor, managing, and/or ASSISTANT NONFICTION EDITOR associate editors. -
Modeling of Metamaterials in Wave Propagation
Modeling of Metamaterials in Wave Propagation G. Leugering, E. Rohan and F. Seifrt Lehrstuhl für Angewandte Mathematik II, Universität Erlangen-Nürnberg, Germany. New Technologies Research Center, Research Institute at University of West Bohemia, Plzen, Czech Re- public. Abstract: This chapter focuses on acoustic, electromagnetic, elastic and piezo-electric wave propagation through heterogenous layers. The motivation is provided by the demand for a better understanding of meta-materials and their possible construction. We stress the analo- gies between the mathematical treatment of phononic, photonic and elastic meta-materials. Moreover, we treat the cloaking problem in more detail from an analytical and simulation oriented point of view. The novelty in the approach presented here is with the interlinked homogenization- and optimization procedure. INTRODUCTION as ’negative Poisson’ ratio in elastic material foams, negative ’mass’ and ’negative refraction indices’ for The terminology ’metamaterials’ refers to ’beyond the forming of band-gaps in acoustic and optical de- conventional material properties’ and consequently vices, respectively. those ’materials’ typically are not found in nature. Thus given acoustic, elasto-dynamic, piezo-electric It comes as no surprise that research in this area, or electromagnetic wave propagation in a non- once the first examples became publicly known, has homogeneous medium and given a certain merit undergone an exponential growth. Metamaterials function describing the desired material-property or are most often man-made, are engineered materi- dynamic performance of the body involved, one als with a wide range of applications. Starting in wants to find e.g. the location, size, shape and the area of micro-waves where one aims at cloak- material properties of small inclusions such that ing objects from electromagnetic waves in the in- the merit function is increased towards an opti- visible frequency range, the ideas rather quickly in- mal material or performance. -
The Predator Script
THE PREDATOR by Shane Black & Fred Dekker Based on the characters created by Jim Thomas & John Thomas REVISED DRAFT 04-17-2016 SPACE Cold. Silent. A billion twinkling stars. Then... A bass RUMBLE rises. Becomes a BONE-RATTLING ROAR as -- A SPACECRAFT RACHETS PAST CAMERA, fuel cables WHIPPING into frame, torn loose! Titanium SCREAMS as the ship DETACHES VIOLENTLY; shards CASCADING in zero gravity--! (NOTE: For reasons that will become apparent, we let us call this vessel “THE ARK.”) WIDER - THE ARK as it HURTLES AWAY from a docking gantry underneath a vastly LARGER SHIP it was attached to. Wobbly. Desperate. We’re witnessing a HIJACK. WIDER STILL - THE PREDATOR MOTHER SHIP DWARFS the escaping vessel. Looming; like a nautilus of molded black steel. INT. PREDATOR MOTHER SHIP Backed by the glow of compu-screens, a half-glimpsed alien -- A PREDATOR -- watches the receding ARK through a viewport. (NOTE: we see him mostly in shadow, full reveal to come). INT. SMALLER VESSEL (ARK) Emergency lights illuminate a dank, organic-looking interior. CAMERA MOVES PAST: EIGHT STASIS CYLINDERS Around the periphery. FROST clouds the cryotubes, prevents us from seeing the “passengers.” Finally, CAMERA ARRIVES AT -- A HULKING, DREAD-LOCKED FIGURE The pilot of this crippled ship. We do not see him fully either, but for the record? This is our “GOOD” PREDATOR.” HIS TALONS dance across a control panel; a shrill beep..! Predator symbols, but we get the idea: ERROR--ERROR--ERROR-- Our Predator TAPS more controls. Feverish. Until -- EXT. ARK A final tether COMES LOOSE, venting PLASMA energy, and -- 2. -
Do Cloaked Objects Really Scatter Less?
Do Cloaked Objects Really Scatter Less? Francesco Monticone and Andrea Alù* Department of Electrical and Computer Engineering, The University of Texas at Austin, 1 University Station C0803, Austin, Texas 78712, USA *[email protected] We discuss the global scattering response of invisibility cloaks over the entire frequency spectrum, from static to very high frequencies. Based on linearity, causality and energy conservation we show that the total extinction and scattering, integrated over all wavelengths, of any linear, passive, causal and non-diamagnetic cloak necessarily increases compared to the uncloaked case. In light of this general principle, we provide a quantitative measure to compare the global performance of different cloaking techniques and we discuss solutions to minimize the global scattering signature of an object using thin, superconducting shells. Our results provide important physical insights on how invisibility cloaks operate and affect the global scattering of an object, suggesting ways to defeat countermeasures aimed at detecting cloaked objects using short impinging pulses. I. INTRODUCTION The last decade has witnessed a significant progress in the field of classical electrodynamic theory and applications, following the introduction and development of the concept of metamaterials. This field of research has provided a new theoretical framework and practical tools to control electromagnetic waves and fields in unprecedented ways, beyond what is directly offered by natural materials [1]. Among a broad landscape of -
Wsn 47(2) (2016) 75-88 Eissn 2392-2192
Available online at www.worldscientificnews.com WSN 47(2) (2016) 75-88 EISSN 2392-2192 Acoustic cylindrical cloak S. M. Premarathna, K. A. I. L. Wijewardena Gamalath* Department of Physics, University of Colombo, Colombo 3, Sri Lanka *E-mail address: [email protected] ABSTRACT Using the analogy between anisotropic acoustic metamaterials with magnetic metamaterials in transverse magnetic mode, an electromagnetic wave of 2 GHz n transverse magnetic mode, at normal incidence propagating through a two dimensional, anisotropic, semi infinite, double negative, metamaterial slab of 800 × 800 cells, embedded in free space, for the ideal loss case was simulated by a radially dependent finite difference time dependent method to study an ideal acoustic cylindrical cloak. For the simulations multiple cycle m-n-m pulses generating Gaussian beams were used as sinusoidal hard line sources. The simulations for acoustic cylindrical cloaking by a reduced parameter model and a higher order parameter model are also presented. The cloaking behaviour is largely dependent upon the transformation and not on the thickness of the cloak. The radial dependent model and the higher order transformation model are suited for acoustic cloaking. Keywords: Acoustic metamaterials; electromagnetic metamaterials; negative index; anisotropic’ cloaking, radially dependent FDTD method; reduced parameter model’ higher order parameter model 1. INTRODUCTION The purpose of a cloaking device is to define a region of space invisibly isolated from passing acoustic waves. This is accomplished by manipulating the paths traversed by sound through a novel acoustic material. Although the objects in the defined location are still present, the incident waves are guided around them without being affected by the object itself. -
Dragon Magazine
Blastoff! The STAR FRONTIERS™ game pro- The STAR FRONTIERS set includes: The work ject was ambitious from the start. The A 16-page Basic Game rule book problems that appear when designing A 64-page Expanded Game rule three complete and detailed alien cul- book tures, a huge frontier area, futuristic is done — A 32-page introductory module, equipment and weapons, and the game Crash on Volturnus rules that make all these elements work now comes 2 full-color maps, 23” x 35” together, were impossible to predict and 10¾" by 17" and not easy to overcome. But the dif- A sheet of 285 full-color counters the fun ficulties were resolved, and the result is a game that lets players enter a truly wide-open space society and explore, The races wander, fight, trade, or adventure A quartet of intelligent, starfaring by Steve Winter through it in the best science-fiction races inhabit the STAR FRONTIERS tradition. rules. New player characters can be D RAGON 7 members of any one of these groups: The adventure ple who had never played a wargame or a Humans (basically just like you With the frontier as its background, role-playing game before. In order to tap and me) the action in a STAR FRONTIERS game this huge market, TSR decided to re- Vrusk (insect-like creatures with focuses on exploring new worlds, dis- structure the STAR FRONTIERS game 10 limbs) covering alien secrets or unearthing an- so it would appeal to people who had Yazirians (ape-like humanoids cient cultures. The rule book includes never seen this type of game. -
Electromagnetic Description and Unexpected Effects
Metamaterials and composites: electromagnetic description and unexpected effects IEEE AP-Society Distinguished Lecture Hong Kong Chapter — 2 March 2015 City University of Hong Kong Ari Sihvola Aalto University Department of Radio Science and Engineering Finland FINLAND ESPOO Annual Meeting of the American Physical Society 29 December 1959 There’s plenty of room at the bottom! Today’s keywords • scales & levels • geometry–matter interaction • emergence/enhancement of losses • effective description and complex constitutive relations • mixing rules METAMATERIALS ? METAMATERIALS ? Wikipedia definition (changing…) 2006: In electromagnetism (covering areas like optics and photonics), a meta material (or metamaterial) is an object that gains its (electromagnetic) material properties from its structure rather than inheriting them directly from the materials it is composed of. This term is particularly used when the resulting material has properties not found in naturally-formed substances. 2014: Metamaterials gain their properties not from their composition, but from their exactingly-designed structures. Their precise shape, geometry, size, orientation and arrangement can affect the waves of light or sound in an unconventional manner, creating material properties which are unachievable with conventional materials. A. Sihvola (2003): Electromagnetic emergence in metamaterials, in Advances in Electomagnetics of Complex Media and Metamaterials, (S. Zouhdi et al., eds), NATO Science Series, 89, 1-17. A. Sihvola (2007): Metamaterials in electromagnetics. Metamaterials, 1, 2-11. Scales in (electromagnetic) material modeling İ ȝ ȟ ȗ Collection of dipole and multipole moments Physical structure (meta)material levels and phenomena • materialization • mathematization • realization • idealization • synthetization • projection • localization • homogenization • fabrication • parametrization • modularization - non-unique - wash-out of microsopic structure - several realizations - loss of details - multiple platforms - emergence, paradigm change For example, in EE context.. -
TAG, It's You! a NEW SPIN on an OLD GAME
Student Life Magazine The University of Advancing Technology Issue 5 SUMMER/FALL 2009 03 TAG, IT’S YOU A New Spin on an Old Game S N A P I T 50 D IGITAL DREAMS DO COME TRUE a Western Short FILM Destined for Greatness 24 Rise to The Surface Three Students Build a Multi-Touch Computer $6.95 SUMMER/FALL T.O.C. • • • LOOK FOR THESE MICROSOFT TAGS 04 TAG, IT'S YOU! A NEW SPIN ON AN OLD GAME TA B L E O F CON T E N T S GEEK 411 ISSUE 5 SUMMER/FALL 2009 ABOUT UAT 10 WE’RE TAKING OVER THE WORLD. JOIN US. 32 GET GEEKALICIOUS: T-SHIRT SALE 41 THE BRICKS (OUR AWESOME FACULTY) 49 THE MORTAR (OUR AWESOME STAFF) INSIDE THE TECH WORLD FEATURE 6 BIG BRAIN EVENTS STORIES 26 DEADLY TALENTED ALUMNI 35 WHAT'S YOUR GEEK IQ? 36 GO PLAY WITH YOUR DOTS 24 RISE TO THE SURFACE 38 WHAT’S HOT, WHAT’S NOT ThE RE STUDENTS BUILD A MULTI-TOUCH COMPUTER 42 DAYS OF FUTURE PAST 45 GADGETS & GIZMOS GEEK ESSENTIALS 12 GEEKS ON TOUR 18 DAY IN THE LIFE OF A DORM GEEK 30 LET THE TECH GAMES BEGIN 40 YOU KNOW YOU WANT THIS 46 HOW WE GOT SO AWESOME 47 WE GOT WHAT YOU NEED 22 GEEKILY EVER AFTER 54 GEEKS UNITE – CLUBS AND GROUPS HWTOO W UAT STUDENTS FELL IN LOVE AT FIRST SHOT STORIES ABOUT REALLY SMART PEOPLE 8 INVASION OF THE STAY PUFT BUNNY 29 RAY KURZWEIL 34 GEEK BLOGS 50 COWBOY DREAMS 20 DAVID WESSMAN IS THE MAN UAP T ROFESSOR DIRECTS FILM 16 LIVING THE GEEK DREAM 33 INTRODUCING… NEW GEEKS 14 WE DO STUFF THAT MATTERS 2 | GEEK 411 | UAT STUDENT LIFE MAGAZINE 09UT A 151 © CONTENTS COPYRIGHT BY FABCOM 20092008 LOOK FOR THESE MICROSOFT TAGS THROUGHOUT THIS S ISSUE OF GEEK 411 N AND TAG THEM A P TO GET MORE OF I THE STORY OR T BONUS CONTENT. -
Cracking the Invisibility Code
GLobaL AFFairs_INVISIBILITY / FASTFORWARD CRACKING THE INVISIBILITY CODE PULLING OFF A DISAppEARING act could soon become a reality as the world awaits a defining moment. BY ROHIT BASU emember Dr. Sebastian Caine, a brilliant but Potter. egotistical scientist in Hollow Man, a Holly- Be that as it may in the realm of popular culture, in- wood blockbuster that captured global ima- visibility has been the fountainhead of several research ini- gination in 2000? Dr. Caine, commissioned tiatives in recent times. by the U.S. military, discovers a serum for Ulf Leonhardt and the group led by Sir John Pendry, invisibility to aid and abet Pentagon’s war a theoretical physicist associated with Cambridge Univer- games. Hell-bent on achieving the ultimate breakthrough, sity, had come up with the theoretical concept of invisibil- Rhe pushes his team of researchers to use him as a subject ity devices, which was followed by a demonstration of the for the experiment. The test turns out to be a success. Ho- first practical ‘Invisibility Cloak’. wever, the formula affects not only his external physical Ulf took to geometry while teaching Albert Einstein’s nature, but also morphs the internal personality, triggering Theory of General Relativity in Ulm, Germany, about a a series of cataclysmic events. decade ago. Incidentally, Einstein, too, was born in Ulm. In The reel world has often been inspired by the real. retrospect, Ulf didn’t imbibe textbook knowledge of general Scientists across the globe are on a quest to crack the invis- relativity, but came to terms with the fascinating theory ibility code. -
Metamaterials for Space Applications Final Report
Metamaterials for Space Applications Design of invisibility cloaks for reduced observability of objects Final Report Authors: F. Bilotti, S. Tricarico, L. Vegni Affiliation: University Roma Tre ESA Researcher(s): Jose M. Llorens and Luzi Bergamin Date: 20.7.2008 Contacts: Filiberto Bilotti Tel: +39.06.57337096 Fax: +39.06.57337026 e-mail: [email protected] Leopold Summerer Tel: +31(0)715655174 Fax: +31(0)715658018 e-mail: [email protected] Ariadna ID: 07/7001b Study Duration: 4 months Available on the ACT website http://www.esa.int/act Contract Number: 21263/07/NL/CB Contents Abstract ...................................................................................................................3 Objectives of the study .........................................................................................4 1 Design of Invisibility Cloaks at Microwaves ..............................................7 1.1 Cloak with ENZ materials at microwaves...................................................... 7 1.2 Cloak with MNZ materials at microwaves ................................................... 12 1.3 Full wave simulations of an ideal MNZ-ENZ cloak at microwaves.......... 15 1.4 Design of an MNZ-ENZ cloak at microwaves with magnetic inclusions 21 2 Design of a cloak with ENZ metamaterials at THz and/or optical frequencies............................................................................................................ 26 3 Reduction of the radiation pressure by optical cloaking ...................... 34 4 Conclusions.................................................................................................. -
Foundation the International Review of Science Fiction Foundation 119 the International Review of Science Fiction
Foundation The International Review of Science Fiction Foundation 119 The International Review of Science Fiction In this issue: Matt Englund reassesses Philip K. Dick’s Galactic Pot Healer George A. Gonzalez explores US military policy in Star Trek Foundation Samantha Kountz analyses the representation of immigration in post-war sf cinema Erica Moore evaluates the post-Darwinism of J.G. Ballard’s Crash Nick Hubble reflects on the legacy of 2000 AD Iain M. Banks and Kim Stanley Robinson in conversation on the subject of utopia Vol. 43 No.119 2014 43 No.119 Vol. Conference reports by Paul Kincaid, Paul March-Russell and Robin Anne Reid In addition, there are reviews by: Jeremy Brett, Molly Cobb, Leimar Garcia-Siino, Lincoln Geraghty, Grace Halden, Andrew Hedgecock, Anna McFarlane, Joe Norman, Andy Sawyer, Will Slocombe, Tom Sykes and Michelle K. Yost Of books by: Jeannette Baxter and Rowland Wymer, David Brittain, Stefan Ekman, Simon Ings, Graham Joyce, Paul McAuley, Howard E. McCurdy, Jonathan Oliver, Christopher Sims, Graham Sleight, David C. Smith, and Thomas Van Parys and I.Q. Hunter Cover image/credit: Ian Gibson Foundation is published three times a year by the Science Fiction Foundation (Registered Charity no. 1041052). It is typeset and printed by The Lavenham Press Ltd., 47 Water Street, Lavenham, Suffolk, CO10 9RD. Foundation is a peer-reviewed journal. Subscription rates for 2015 Individuals (three numbers) United Kingdom £20.00 Europe (inc. Eire) £22.00 Rest of the world £25.00 / $42.00 (U.S.A.) Student discount £14.00 / $23.00 (U.S.A.) Institutions (three numbers) Anywhere £42.00 / $75.00 (U.S.A.) Airmail surcharge £7.00 / $12.00 (U.S.A.) Single issues of Foundation can also be bought for £7.00 / $15.00 (U.S.A.). -
Control of the Electromagnetic Fields by Metamaterials
International Journal of Research Studies in Electrical and Electronics Engineering(IJRSEEE) Volume 4, Issue 1, 2018, PP 9-23 ISSN 2454-9436 (Online) DOI: http://dx.doi.org/10.20431/2454-9436.0401002 www.arcjournals.org Control of the Electromagnetic Fields by Metamaterials Tatjana Gric1, Aleksej Trofimov1 1Vilnius Gediminas Technical University *Corresponding Author: Dr. Tatjana Gric, Vilnius Gediminas Technical University, Lithuania. Abstract: Metamaterials are engineered composites. Much of the effort in the electrical engineering, material science, physics, and optics communities emphasized constructing efficient metamaterials and using them for potentially novel applications in antenna and radar design, subwavelength imaging, and invisibility cloak design. The purpose of this chapter is to provide a detailed introduction to the basic metamaterial modelling approaches and an overview of innovative phenomena enabled by metamaterials. While high tunability of the electromagnetic properties might be provided by metamaterial structures and metasurfaces, the former option has not yet been used to solve this problem. By means of the freedom of design provided by metamaterials, we propose the ways to redirect electromagnetic fields and demonstrate a design strategy. Keywords: Metamaterial, electromagnetic field, cloaking 1. INTRODUCTION Metamaterials are engineered composites [1-3]. Much of the effort in the electrical engineering, material science, physics, and optics communities emphasized constructing efficient metamaterials and using them for potentially novel applications in antenna and radar design, subwavelength imaging, and invisibility cloak design [4, 5]. The purpose of this chapter is to provide a detailed introduction to the basic metamaterial modelling approaches and an overview of innovative phenomena enabled by metamaterials. While high tunability of the electromagnetic properties might be provided by metamaterial structures and metasurfaces, the former option has not yet been used to solve this problem.