Chapter 8 Waveguides and Resonators
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Lecture 17 - Rectangular Waveguides/Photonic Crystals� and Radiative Recombination -Outline�
6.772/SMA5111 - Compound Semiconductors Lecture 17 - Rectangular Waveguides/Photonic Crystals� and Radiative Recombination -Outline� • Dielectric optics (continuing discussion in Lecture 16) Rectangular waveguides� Coupled rectangular waveguide structures Couplers, Filters, Switches • Photonic crystals History: Optical bandgaps and Eli Yablonovich, to the present One-dimensional photonic crystals� Distributed Bragg reflectors� Photonic fibers; perfect mirrors� Two-dimensional photonic crystals� Guided wave optics structures� Defect levels� Three-dimensional photonic crystals • Recombination Processes (preparation for LEDs and LDs) Radiative vs. non-radiative� Relative carrier lifetimes� C. G. Fonstad, 4/03 Lecture 17 - Slide 1 Absorption in semiconductors - indirect-gap band-to-band� •� The phonon modes involved indirect band gap absorption •� Dispersion curves for acoustic and optical phonons Approximate optical phonon energies for several semiconductors Ge: 37 meV (Swaminathan and Macrander) Si: 63 meV GaAs: 36 meV C. G. Fonstad, 4/03� Lecture 15 - Slide 2� Slab dielectric waveguides� •�Nature of TE-modes (E-field has only a y-component). For the j-th mode of the slab, the electric field is given by: - (b -w ) = j j z t E y, j X j (x)Re[ e ] In this equation: w: frequency/energy of the light pw = n = l 2 c o l o: free space wavelength� b j: propagation constant of the j-th mode Xj(x): mode profile normal to the slab. satisfies d 2 X j + 2 2- b 2 = 2 (ni ko j )X j 0 dx where:� ni: refractive index in region i� ko: propagation constant in free space = pl ko 2 o C. G. Fonstad, 4/03� Lecture 17 - Slide 3� Slab dielectric waveguides� •�In approaching a slab waveguide problem, we typically take the dimensions and indices in the various regions and the free space wavelength or frequency of the light as the "givens" and the unknown is b, the propagation constant in the slab. -
The Green-Function Transform and Wave Propagation
1 The Green-function transform and wave propagation Colin J. R. Sheppard,1 S. S. Kou2 and J. Lin2 1Department of Nanophysics, Istituto Italiano di Tecnologia, Genova 16163, Italy 2School of Physics, University of Melbourne, Victoria 3010, Australia *Corresponding author: [email protected] PACS: 0230Nw, 4120Jb, 4225Bs, 4225Fx, 4230Kq, 4320Bi Abstract: Fourier methods well known in signal processing are applied to three- dimensional wave propagation problems. The Fourier transform of the Green function, when written explicitly in terms of a real-valued spatial frequency, consists of homogeneous and inhomogeneous components. Both parts are necessary to result in a pure out-going wave that satisfies causality. The homogeneous component consists only of propagating waves, but the inhomogeneous component contains both evanescent and propagating terms. Thus we make a distinction between inhomogenous waves and evanescent waves. The evanescent component is completely contained in the region of the inhomogeneous component outside the k-space sphere. Further, propagating waves in the Weyl expansion contain both homogeneous and inhomogeneous components. The connection between the Whittaker and Weyl expansions is discussed. A list of relevant spherically symmetric Fourier transforms is given. 2 1. Introduction In an impressive recent paper, Schmalz et al. presented a rigorous derivation of the general Green function of the Helmholtz equation based on three-dimensional (3D) Fourier transformation, and then found a unique solution for the case of a source (Schmalz, Schmalz et al. 2010). Their approach is based on the use of generalized functions and the causal nature of the out-going Green function. Actually, the basic principle of their method was described many years ago by Dirac (Dirac 1981), but has not been widely adopted. -
Approximate Separability of Green's Function for High Frequency
APPROXIMATE SEPARABILITY OF GREEN'S FUNCTION FOR HIGH FREQUENCY HELMHOLTZ EQUATIONS BJORN¨ ENGQUIST AND HONGKAI ZHAO Abstract. Approximate separable representations of Green's functions for differential operators is a basic and an important aspect in the analysis of differential equations and in the development of efficient numerical algorithms for solving them. Being able to approx- imate a Green's function as a sum with few separable terms is equivalent to the existence of low rank approximation of corresponding discretized system. This property can be explored for matrix compression and efficient numerical algorithms. Green's functions for coercive elliptic differential operators in divergence form have been shown to be highly separable and low rank approximation for their discretized systems has been utilized to develop efficient numerical algorithms. The case of Helmholtz equation in the high fre- quency limit is more challenging both mathematically and numerically. In this work, we develop a new approach to study approximate separability for the Green's function of Helmholtz equation in the high frequency limit based on an explicit characterization of the relation between two Green's functions and a tight dimension estimate for the best linear subspace approximating a set of almost orthogonal vectors. We derive both lower bounds and upper bounds and show their sharpness for cases that are commonly used in practice. 1. Introduction Given a linear differential operator, denoted by L, the Green's function, denoted by G(x; y), is defined as the fundamental solution in a domain Ω ⊆ Rn to the partial differ- ential equation 8 n < LxG(x; y) = δ(x − y); x; y 2 Ω ⊆ R (1) : with boundary condition or condition at infinity; where δ(x − y) is the Dirac delta function denoting an impulse source point at y. -
Waves and Imaging Class Notes - 18.325
Waves and Imaging Class notes - 18.325 Laurent Demanet Draft December 20, 2016 2 Preface In the margins of this text we use • the symbol (!) to draw attention when a physical assumption or sim- plification is made; and • the symbol ($) to draw attention when a mathematical fact is stated without proof. Thanks are extended to the following people for discussions, suggestions, and contributions to early drafts: William Symes, Thibaut Lienart, Nicholas Maxwell, Pierre-David Letourneau, Russell Hewett, and Vincent Jugnon. These notes are accompanied by computer exercises in Python, that show how to code the adjoint-state method in 1D, in a step-by-step fash- ion, from scratch. They are provided by Russell Hewett, as part of our software platform, the Python Seismic Imaging Toolbox (PySIT), available at http://pysit.org. 3 4 Contents 1 Wave equations 9 1.1 Physical models . .9 1.1.1 Acoustic waves . .9 1.1.2 Elastic waves . 13 1.1.3 Electromagnetic waves . 17 1.2 Special solutions . 19 1.2.1 Plane waves, dispersion relations . 19 1.2.2 Traveling waves, characteristic equations . 24 1.2.3 Spherical waves, Green's functions . 29 1.2.4 The Helmholtz equation . 34 1.2.5 Reflected waves . 35 1.3 Exercises . 39 2 Geometrical optics 45 2.1 Traveltimes and Green's functions . 45 2.2 Rays . 49 2.3 Amplitudes . 52 2.4 Caustics . 54 2.5 Exercises . 55 3 Scattering series 59 3.1 Perturbations and Born series . 60 3.2 Convergence of the Born series (math) . 63 3.3 Convergence of the Born series (physics) . -
Lecture 26 Dielectric Slab Waveguides
Lecture 26 Dielectric Slab Waveguides In this lecture you will learn: • Dielectric slab waveguides •TE and TM guided modes in dielectric slab waveguides ECE 303 – Fall 2005 – Farhan Rana – Cornell University TE Guided Modes in Parallel-Plate Metal Waveguides r E()rr = yˆ E sin()k x e− j kz z x>0 o x x Ei Ei r r Ey k E r k i r kr i H Hi i z ε µo Hr r r ki = −kx xˆ + kzzˆ kr = kx xˆ + kzzˆ Guided TE modes are TE-waves bouncing back and fourth between two metal plates and propagating in the z-direction ! The x-component of the wavevector can have only discrete values – its quantized m π k = where : m = 1, 2, 3, x d KK ECE 303 – Fall 2005 – Farhan Rana – Cornell University 1 Dielectric Waveguides - I Consider TE-wave undergoing total internal reflection: E i x ε1 µo r k E r i r kr H θ θ i i i z r H r ki = −kx xˆ + kzzˆ r kr = kx xˆ + kzzˆ Evanescent wave ε2 µo ε1 > ε2 r E()rr = yˆ E e− j ()−kx x +kz z + yˆ ΓE e− j (k x x +kz z) 2 2 2 x>0 i i kz + kx = ω µo ε1 Γ = 1 when θi > θc When θ i > θ c : kx = − jα x r E()rr = yˆ T E e− j kz z e−α x x 2 2 2 x<0 i kz − α x = ω µo ε2 ECE 303 – Fall 2005 – Farhan Rana – Cornell University Dielectric Waveguides - II x ε2 µo Evanescent wave cladding Ei E ε1 µo r i r k E r k i r kr i core Hi θi θi Hi ε1 > ε2 z Hr cladding Evanescent wave ε2 µo One can have a guided wave that is bouncing between two dielectric interfaces due to total internal reflection and moving in the z-direction ECE 303 – Fall 2005 – Farhan Rana – Cornell University 2 Dielectric Slab Waveguides W 2d Assumption: W >> d x cladding y core -
Summary of Wave Optics Light Propagates in Form of Waves Wave
Summary of Wave Optics light propagates in form of waves wave equation in its simplest form is linear, which gives rise to superposition and separation of time and space dependence (interference, diffraction) waves are characterized by wavelength and frequency propagation through media is characterized by refractive index n, which describes the change in phase velocity media with refractive index n alter velocity, wavelength and wavenumber but not frequency lenses alter the curvature of wavefronts Optoelectronic, 2007 – p.1/25 Syllabus 1. Introduction to modern photonics (Feb. 26), 2. Ray optics (lens, mirrors, prisms, et al.) (Mar. 7, 12, 14, 19), 3. Wave optics (plane waves and interference) (Mar. 26, 28), 4. Beam optics (Gaussian beam and resonators) (Apr. 9, 11, 16), 5. Electromagnetic optics (reflection and refraction) (Apr. 18, 23, 25), 6. Fourier optics (diffraction and holography) (Apr. 30, May 2), Midterm (May 7-th), 7. Crystal optics (birefringence and LCDs) (May 9, 14), 8. Waveguide optics (waveguides and optical fibers) (May 16, 21), 9. Photon optics (light quanta and atoms) (May 23, 28), 10. Laser optics (spontaneous and stimulated emissions) (May 30, June 4), 11. Semiconductor optics (LEDs and LDs) (June 6), 12. Nonlinear optics (June 18), 13. Quantum optics (June 20), Final exam (June 27), 14. Semester oral report (July 4), Optoelectronic, 2007 – p.2/25 Paraxial wave approximation paraxial wave = wavefronts normals are paraxial rays U(r) = A(r)exp(−ikz), A(r) slowly varying with at a distance of λ, paraxial Helmholtz equation -
High Gain Slotted Waveguide Antenna Based on Beam Focusing Using Electrically Split Ring Resonator Metasurface Employing Negative Refractive Index Medium
Progress In Electromagnetics Research C, Vol. 79, 115–126, 2017 High Gain Slotted Waveguide Antenna Based on Beam Focusing Using Electrically Split Ring Resonator Metasurface Employing Negative Refractive Index Medium Adel A. A. Abdelrehim and Hooshang Ghafouri-Shiraz* Abstract—In this paper, a new high performance slotted waveguide antenna incorporated with negative refractive index metamaterial structure is proposed, designed and experimentally demonstrated. The metamaterial structure is constructed from a multilayer two-directional structure of electrically split ring resonator which exhibits negative refractive index in direction of the radiated wave propagation when it is placed in front of the slotted waveguide antenna. As a result, the radiation beams of the slotted waveguide antenna are focused in both E and H planes, and hence the directivity and the gain are improved, while the beam area is reduced. The proposed antenna and the metamaterial structure operating at 10 GHz are designed, optimized and numerically simulated by using CST software. The effective parameters of the eSRR structure are extracted by Nicolson Ross Weir (NRW) algorithm from the s-parameters. For experimental verification, a proposed antenna operating at 10 GHz is fabricated using both wet etching microwave integrated circuit technique (for the metamaterial structure) and milling technique (for the slotted waveguide antenna). The measurements are carried out in an anechoic chamber. The measured results show that the E plane gain of the proposed slotted waveguide antenna is improved from 6.5 dB to 11 dB as compared to the conventional slotted waveguide antenna. Also, the E plane beamwidth is reduced from 94.1 degrees to about 50 degrees. -
Waveguide Direction User Manual
WaveGuide Direction Ex. Certified User Manual WaveGuide Direction Ex. Certified User Manual Applicable for product no. WG-DR40-EX Related to software versions: wdr 4.#-# Version 4.0 21st of November 2016 Radac B.V. Elektronicaweg 16b 2628 XG Delft The Netherlands tel: +31(0)15 890 3203 e-mail: [email protected] website: www.radac.nl Preface This user manual and technical documentation is intended for engineers and technicians involved in the software and hardware setup of the Ex. certified version of the WaveGuide Direction. Note All connections to the instrument must be made with shielded cables with exception of the mains. The shielding must be grounded in the cable gland or in the terminal compartment on both ends of the cable. For more information regarding wiring and cable specifications, please refer to Chapter 2. Legal aspects The mechanical and electrical installation shall only be carried out by trained personnel with knowledge of the local requirements and regulations for installation of electronic equipment. The information in this installation guide is the copyright property of Radac BV. Radac BV disclaims any responsibility for personal injury or damage to equipment caused by: Deviation from any of the prescribed procedures. • Execution of activities that are not prescribed. • Neglect of the general safety precautions for handling tools and use of electricity. • The contents, descriptions and specifications in this installation guide are subject to change without notice. Radac BV accepts no responsibility for any errors that may appear in this user manual. Additional information Please do not hesitate to contact Radac or its representative if you require additional information. -
High-Index Glass Waveguides for AR Roadmap to Consumer Market
High-Index Glass Waveguides for AR Roadmap to Consumer Market Dr. Xavier Lafosse Commercial Technology Director, Advanced Optics SPIE AR / VR / MR Conference February 2-4, 2020 Outline • Enabling the Display Industry Through Glass Innovations • Our Solutions for Augmented Reality Applications • The Challenges for Scalable and Cost-Effective Solutions Precision Glass Solutions © 2020 Corning Incorporated 2 Corning’s glass innovations have enabled displays for more than 80 years… 1939 1982 2019 Cathode ray tubes for Liquid crystal display (LCD) EAGLE XG® Glass is the black and white televisions glass for monitors, laptops LCD industry standard Precision Glass Solutions © 2020 Corning Incorporated 3 Corning is a world-renowned innovator and supplier across the display industry Cover Glass Glass For AR/MR Display for Display Waveguides Display Technologies Introduced glass panels for 1st active 12 years of innovation in cover Corning Precision Glass Solutions matrix LCD devices in 1980s glass for smartphones, laptops, (PGS) was the first to market with tablets & wearables ultra-flat, high-index wafers for top- Have sold 25 billion square feet of tier consumer electronic companies ® ® ® ® flagship Corning EAGLE XG Corning Gorilla Glass is now on pursuing augmented reality and more than 7 billion devices worldwide mixed reality waveguide displays Precision Glass Solutions © 2020 Corning Incorporated 4 PGS offers best-in-class glass substrates for semiconductor and consumer electronics applications Advanced Low-loss, low Wafer-level Waveguide -
Instruction Manual Waveguide & Waveguide Server
Instruction manual WaveGuide & WaveGuide Server Radac bv Elektronicaweg 16b 2628 XG DELFT Phone: +31 15 890 32 03 Email: [email protected] www.radac.n l Instruction manual WaveGuide + WaveGuide Server Version 4.1 2 of 30 Oct 2013 Instruction manual WaveGuide + WaveGuide Server Version 4.1 3 of 30 Oct 2013 Instruction manual WaveGuide + WaveGuide Server Table of Contents Introduction...................................................................................................................................................................4 Installation.....................................................................................................................................................................5 The WaveGuide Sensor...........................................................................................................................................5 CaBling.....................................................................................................................................................................6 The WaveGuide Server............................................................................................................................................7 Commissioning the system...........................................................................................................................................9 Connect the WGS to a computer.............................................................................................................................9 Authorization.........................................................................................................................................................10 -
Analysis of a Waveguide-Fed Metasurface Antenna
Analysis of a Waveguide-Fed Metasurface Antenna Smith, D., Yurduseven, O., Mancera, L. P., Bowen, P., & Kundtz, N. B. (2017). Analysis of a Waveguide-Fed Metasurface Antenna. Physical Review Applied, 8(5). https://doi.org/10.1103/PhysRevApplied.8.054048 Published in: Physical Review Applied Document Version: Publisher's PDF, also known as Version of record Queen's University Belfast - Research Portal: Link to publication record in Queen's University Belfast Research Portal Publisher rights © 2017 American Physical Society. This work is made available online in accordance with the publisher’s policies. Please refer to any applicable terms of use of the publisher. General rights Copyright for the publications made accessible via the Queen's University Belfast Research Portal is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy The Research Portal is Queen's institutional repository that provides access to Queen's research output. Every effort has been made to ensure that content in the Research Portal does not infringe any person's rights, or applicable UK laws. If you discover content in the Research Portal that you believe breaches copyright or violates any law, please contact [email protected]. Download date:02. Oct. 2021 PHYSICAL REVIEW APPLIED 8, 054048 (2017) Analysis of a Waveguide-Fed Metasurface Antenna † † David R. Smith,* Okan Yurduseven, Laura Pulido Mancera, and Patrick Bowen Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708, USA Nathan B. -
University of California Santa Cruz Distributed Bragg
UNIVERSITY OF CALIFORNIA SANTA CRUZ DISTRIBUTED BRAGG REFLECTOR ON ARROW WAVEGUIDES A thesis submitted in partial satisfaction of the requirements for the degree of BACHELOR OF SCIENCE in PHYSICS by Raul A. Reyes Hueros June 2018 The thesis of Raul A. Reyes Hueros is approved: Professor Robert P. Johnson, Chair Professor Holger Schmidt Professor David Smith Copyright c by Raul A. Reyes Hueros 2018 Abstract Distributed Bragg Reflector on ARROW Waveguides by Raul A. Reyes Hueros A new optofluidic chip design for an on-chip liquid dye laser based on Anti- Resonant Reflecting Optical Waveguides (ARROW) is developed. The microfluidic device is compact, user friendly and, most importantly, can provide the role of a on chip laser. This thesis can be broken into three parts: First, an analysis on distributive feed back (DFB) gratings that is developed to fabricate a optofluidic dye laser from anti-resonant reflecting optical waveguides (ARROW). Second, the reflection spectrum and plausible parameters for the proposed device are simulated with Roaurd's Method. Third, a technique for direct dry transfer of uniform poly (methyl methacrylate) (PMMA) is used to overcome the challenges encountered in conventional PMMA deposition on top of non-flat waveguide structures. Table of Contents Abstract iii List of Figures vi List of Tables viii Acknowledgments ix 1 Introduction 1 1.1 Motivations for Building On-chip Bragg Reflector . 2 1.2 Thesis Organization . 3 2 Background 4 2.1 Distributed Bragg Reflector Gratings . 4 2.2 Organic Dye Molecules . 7 2.2.1 Population Inversion . 7 2.3 Liquid Dye Laser . 9 3 Anti-Resonant Reflecting Optical Waveguides 12 3.1 Theory .