New Laser Technologies Analysis of Quantum Dot and Lithographic Laser Diodes

Total Page:16

File Type:pdf, Size:1020Kb

New Laser Technologies Analysis of Quantum Dot and Lithographic Laser Diodes University of Central Florida STARS Electronic Theses and Dissertations, 2004-2019 2010 New Laser Technologies Analysis Of Quantum Dot And Lithographic Laser Diodes Abdullah Demir University of Central Florida Part of the Electromagnetics and Photonics Commons, and the Optics Commons Find similar works at: https://stars.library.ucf.edu/etd University of Central Florida Libraries http://library.ucf.edu This Doctoral Dissertation (Open Access) is brought to you for free and open access by STARS. It has been accepted for inclusion in Electronic Theses and Dissertations, 2004-2019 by an authorized administrator of STARS. For more information, please contact [email protected]. STARS Citation Demir, Abdullah, "New Laser Technologies Analysis Of Quantum Dot And Lithographic Laser Diodes" (2010). Electronic Theses and Dissertations, 2004-2019. 1561. https://stars.library.ucf.edu/etd/1561 NEW LASER TECHNOLOGIES: ANALYSIS OF QUANTUM DOT AND LITHOGRAPHIC LASER DIODES by ABDULLAH DEMIR B.S. and M.Sc. Koc University 2002, 2005 M.Sc. University of Central Florida 2009 A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the College of Optics and Photonics at the University of Central Florida Orlando, Florida Summer Term 2010 Major Professor: Dennis G. Deppe © 2010 Abdullah Demir ii ABSTRACT The first part of this dissertation presents a comprehensive study of quantum dot (QD) lasers threshold characteristics. The threshold temperature dependence of a QD laser diode is studied in different limits of p-doping, hole level spacing and inhomogeneous broadening. Theoretical analysis shows that the threshold current of a QD laser in the limit of uniform QDs is not temperature independent and actually more temperature sensitive than the quantum well laser. The results also explain the experimental trends of negative characteristic temperature observed in QD lasers and clarify how the carrier distribution mechanisms inside and among the QDs affect the threshold temperature dependence of a QD laser diode. The second part is on the experimental demonstration of lithographic lasers. Today’s vertical-cavity surface-emitting lasers (VCSELs) based on oxide-aperture suffer from serious problems such as heat dissipation, internal strain, reliability, uniformity and size scaling. The lithographic laser provides solutions to all these problems. The transverse mode and cavity are defined using only lithography and epitaxial crystal growth providing simultaneous mode- and current-confinement. Eliminating the oxide aperture is shown to reduce the thermal resistance of the device and leading to increased power density in smaller lasers. When it is combined with better mode matching to gain for smaller devices, high output power density of 58 kW/cm2 is possible for a 3 μm VCSEL with threshold current of 260 μA. These VCSELs also have grating- free single-mode single-polarization emission. The demonstration of lithographic laser diodes with good scaling properties is therefore an important step toward producing ultra-small size laser diodes with high output power density, high speed, high manufacturability and high iii reliability. Lithographic VCSELs ability to control size lithographically in a strain-free, high efficiency device is a major milestone in VCSEL technology. iv To my nieces Fatma and Derya v TABLE OF CONTENTS LIST OF FIGURES..........................................................................................................viii LIST OF TABLES...............................................................................................................x LIST OF ACRONYMS/ABBREVIATIONS.....................................................................xi CHAPTER 1: INTRODUCTION AND OUTLINE .......................................................1 CHAPTER 2: QUANTUM DOT LASER MODEL.......................................................4 2.1 Introduction......................................................................................................................... 4 2.2 Analysis of the Temperature Dependence of Threshold..................................................... 7 2.3 Non-Equilibrium Rate Equation Model............................................................................ 10 2.4 Threshold Temperature Dependence for a QD Laser....................................................... 13 2.5 Summary........................................................................................................................... 16 CHAPTER 3: MODEL IN THE LIMIT OF UNIFORM QUANTUM DOTS ............18 3.1 Introduction....................................................................................................................... 18 3.2 Uniform QDs with Energetically Isolated Ground State Transitions ............................... 21 3.3 Uniform QDs with Multiple Discerete Levels.................................................................. 25 3.4 Summary........................................................................................................................... 30 CHAPTER 4: DESIGN PRINCIPLES OF LITHOGRAPHIC LASER.......................32 4.1 Introduction....................................................................................................................... 32 4.2 Oxide-VCSEL Issues and Limitations.............................................................................. 34 4.3 Optical Mode Confinement............................................................................................... 37 4.4 Current Confinement ........................................................................................................ 40 4.5 Summary........................................................................................................................... 44 CHAPTER 5: EXPERIMENTAL RESULTS ON LITHOGRAPHIC VCSEL ...........45 5.1 Introduction....................................................................................................................... 45 5.2 Device Structure................................................................................................................ 45 vi 5.3 Results............................................................................................................................... 48 5.3.1 Lasing Characteristics...................................................................................... 48 5.3.2 Low Thermal Resistance of Lithographic Structure........................................ 50 5.3.3 High Output Power Density of Small Devices................................................ 52 5.3.4 Single-Mode and Single-Polarization Lasing.................................................. 53 5.3.5 Reliability ........................................................................................................ 57 5.4 Summary........................................................................................................................... 59 CHAPTER 6: SUMMARY...........................................................................................60 LIST OF REFERENCES ..................................................................................................62 vii LIST OF FIGURES Figure 2-1: Atomic force microscope photograph of crystal surface right after QD formation. ..................4 Figure 2-2: Schematic illustration of the energy structure and Fermi levels of two different QDs. Non-equilibrium distribution of electrons is created due to finite carrier relaxation from the barrier and carrier transport between the QDs through wetting layer......................................................5 Figure 2-3: The effect of inhomogeneous broadening on threshold temperature dependence for undoped (squares) and p-doped (circles) QD laser with (a) uniform QDs and (b) inhomogeneously broadened QDs.........................................................................................................15 Figure 3-1: Temperature dependence of dephasing rate. The inset shows the calculated homogeneous broadening at T = −40 °C and T = 40 °C. ......................................................................20 Figure 3-2: Characteristic temperature versus threshold population inversion of p-doped and undoped QD lasers. The inset shows the schematic of QD energy levels with single electron and hole states with acceptor doping. ....................................................................................................22 Figure 3-3: Temperature dependence of normalized threshold current for p-doped planar quantum well and QD lasers.................................................................................................................................24 Figure 3-4: Temperature dependence of threshold current for a multistate undoped QD laser at the 300 K transparency and threshold population inversions of 0.042, 0.113 and 0.182. The T0’s are calculated for 20 °C ≤ T ≤ 80 °C. The inset shows the schematic of energy levels in a multistate QD laser. ...............................................................................................................................26 Figure 3-5: Temperature dependence of threshold current for a multistate undoped QD laser at the 300 K transparency and threshold population inversions of 0.042, 0.113 and 0.182. The T0’s are calculated for 20 °C ≤ T ≤ 80 °C. The inset shows the schematic of energy levels in a multistate QD laser. ...............................................................................................................................28
Recommended publications
  • Monday, 08:00–10:00 CLEO: QELS-Fundamental Science
    07:00–18:00 Registration, Concourse Level Executive Ballroom Executive Ballroom Executive Ballroom Executive Ballroom 210A 210B 210C 210D CLEO: QELS-Fundamental Science 08:00–10:00 08:00–10:00 08:00–10:00 08:00–10:00 FM1A • Quantum FM1B • Topological Photonics I FM1C • Novel Phenomena in FM1D • Coherent Phenomena Optomechanics & Transduction Presider: To Be Announced Classical Nano-Optics in Coupled Resonator Networks Monday, 08:00–10:00 Monday, Presider: Gabriel Molina Terriza; Presider: Mo Mojahedi; Univ. of Presider: To Be Announced Centro de Fisica de Materiales, Toronto, USA Spain FM1A.1 • 08:00 FM1B.1 • 08:00 FM1C.1 • 08:00 FM1D.1 • 08:00 Invited Ultralow Dissipation Mechanical Resona- Spin-Preserving Chiral Photonic Crystal Brightness Theorems for Nanophoton- Solving Hard Computational Problems with 1,2 1 1 tors for Quantum Optomechanics, Nils Mirror, Behrooz Semnani , Jeremy Flan- ics, Hanwen Zhang , Chia Wei Hsu , Owen Coupled Lasers, Nir Davidson1; 1Weizmann 1 1 2 2 2 1 1 Johan Engelsen , Sergey A. Fedorov , Amir nery , Zhenghao Ding , Rubayet Al Maruf , Miller ; Yale Univ., USA. We present nano- Inst. of Science, Israel. We present a new a 1 1 2,1 1 H. Ghadimi , Mohammad J. Bereyhi , Alberto Michal Bajcsy ; ECE, Univ. of Waterloo, photonic ‘’brightness theorems’’, a set of new system of coupled lasers in a modified 1 1 2 2 Beccari , Ryan Schilling , Dalziel J. Wilson , Canada; Inst. for Quantum Computing, power-concentration bounds that generalize degenerate cavity that is used to solve dif- 1 1 Tobias J. Kippenberg ; Ecole Polytechnique Canada. We report on experimental realiza- their ray-optical counterparts, and motivate ficult computational tasks.
    [Show full text]
  • UC Santa Barbara Dissertation Template
    UC Santa Barbara UC Santa Barbara Electronic Theses and Dissertations Title Quantum Dot Lasers for Silicon Photonics Permalink https://escholarship.org/uc/item/8p01r83d Author Norman, Justin Publication Date 2018 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA Santa Barbara Quantum Dot Lasers for Silicon Photonics A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Materials by Justin Colby Norman Committee in charge: Professor John Bowers, Co-Chair Professor Arthur Gossard, Co-Chair Professor Chris Palmstrøm Professor Dirk Bouwmeester December 2018 The dissertation of Justin Colby Norman is approved. ____________________________________________ Professor Dirk Bouwmeester ____________________________________________ Professor Chris Palmstrøm Professor Arthur Gossard, Committee Co-Chair ____________________________________________ Professor John Bowers, Committee Co-Chair December 2018 Quantum Dot Lasers for Silicon Photonics Copyright © 2018 by Justin Colby Norman iii Dedicated to April Norman iv ACKNOWLEDGEMENTS If a thesis were like a journal article and all contributors given credit in the author list, then my title page would exceed entire length of this body of work. Pursuing a Ph.D. is not a simple endeavor, and its pursuit begins long before a student begins their journey in graduate school. To do proper justice to everyone in my life who contributed to my efforts would not be possible in the limited scope of this document, but I will attempt to acknowledge the key individuals who got me here, helped along the way in my scientific endeavors, and who helped me maintain the tenuous grip on sanity inherent to graduate studies.
    [Show full text]
  • Symposium on Undergraduate Research
    SYMPOSIUM ON UNDERGRADUATE RESEARCH Division of Laser Science of A.P.S - LS XXXIV - 17 September 2018.- Washington DC PARTICIPANTS’ LUNCHEON - Ballroom East - 12:00 The participants' luncheon will bring together the Symposium students and distinguished laser scientists. Sandwich lunches will be provided for participants and invited guests only. REMINDER: Group Photo Break 3:55 PM - PLEASE assemble at the designated place!!! POSTER SESSION - International Ballroom East - 1:00 Session LM4G (poster) 1:00 - 3:55 PM, Ballroom East – Dr. Keith Stein, Bethel Univ., Presider LM4G - 1 Using the Instantaneous Velocity of a Brownian Particle in an Optical Tweezer to Measure Changes in Mass. Gabriel H. Alvarez1, Julia E. Orenstein2, Lichung Ha2, Diney S. Ether Jr.2, and Mark G. Raizen2. 1) Stanford Univ., Stanford, CA 94305, 2) Univ. of Texas, Austin, TX 78712. Using a fast detector to observe the light deflected by silica mi- crospheres trapped in an optical tweezer, we obtain positional information from which instantaneous velocities are calcu- lated and fit to the Maxwell-Boltzmann distribution to extract mass. We plan to use this technology to characterize the onset of heterogeneous ice nucleation. LM4G - 2 Optical Tweezing Experiments with Dielectric Microbeads Willa Dworschack1,2, Chiu Yin Lee1, Perri Zilberman1, Martin Cohen1, Harold Metcalf 11) Stony Brook Univ., Stony Brook, NY 11794, 2) Lawrence Univ., Appleton, WI 54911 Optical tweezing utilizes the momentum carried by light to manipulate micro-scale objects. We designed and constructed an optical tweezing apparatus that enabled precision control of dielectric microbeads using a He-Ne laser and an inverted microscope. Its piconewton force capabilities were demonstrated.
    [Show full text]
  • Development of Indium Arsenide Quantum Dot Solar Cells for High Conversion Efficiency Mohamed El-Emawy
    University of New Mexico UNM Digital Repository Electrical and Computer Engineering ETDs Engineering ETDs 1-29-2009 Development of indium arsenide quantum dot solar cells for high conversion efficiency Mohamed El-Emawy Follow this and additional works at: https://digitalrepository.unm.edu/ece_etds Recommended Citation El-Emawy, Mohamed. "Development of indium arsenide quantum dot solar cells for high conversion efficiency." (2009). https://digitalrepository.unm.edu/ece_etds/73 This Thesis is brought to you for free and open access by the Engineering ETDs at UNM Digital Repository. It has been accepted for inclusion in Electrical and Computer Engineering ETDs by an authorized administrator of UNM Digital Repository. For more information, please contact [email protected]. Mohamed Abdel Rahman El-Emawy Candidat e Department of Electrical and Computer Engineering Departmen t This thesis is approved, and it is acceptable in quality and form for publication on microfilm: Appro ved by the Thesis Committee: Prof. Luke F. Lester , Chairperson Dr. Andreas Stintz Dr. Frederic Grillot Dr. Ganesh Balakrishnan Accepted: Dean, Graduate School Date DEVELOPMENT OF INDIUM ARSENIDE QUANTUM DOT SOLAR CELLS FOR HIGH CONVERSION EFFICIENCY BY MOHAMED ABDEL RAHMAN EL-EMAWY B.S., ELECTRICAL ENGINEERING, UNIVERSITY OF NEW MEXICO, 2006 THESIS Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science Electrical Engineering The University of New Mexico Albuquerque, New Mexico December, 2008 ©2008 , Mohamed Abdel Rahman El-Emawy iii DEDICATION To My Parents iv ACKNOWLEDGMENTS I would like to express my thanks to my advisor Professor Luke F. Lester for his guidance and assistance over the course of my research at the Center for High Technology Materials (CHTM).
    [Show full text]
  • III-NITRIDE SELF-ASSEMBLED QUANTUM DOT LIGHT EMITTING DIODES and LASERS by Animesh Banerjee a Dissertation Submitted in Partial
    III-NITRIDE SELF-ASSEMBLED QUANTUM DOT LIGHT EMITTING DIODES AND LASERS by Animesh Banerjee A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Electrical Engineering) in The University of Michigan 2014 Doctoral Committee: Professor Pallab K. Bhattacharya, Chair Associate Professor Pei-Cheng Ku Professor Joanna Mirecki-Millunchick Professor Jamie D. Phillips Animesh Banerjee © 2014 All Rights Reserved To my parents who have always stood by me, and have showered their blessings, unconditional love and unwavering support ii ACKNOWLEDGMENT I would like to express my sincere gratitude to my advisor Prof. Pallab Bhattacharya for his continuous support and motivation, his immense knowledge, enthusiasm and patience powering me along the way during my PhD years. He is a great motivator and educator. He was always available to discuss my research and any technical problem that I encountered. His sheer persistence and determination in solving any problem is something I really admire and aspire to pursue for the rest of my life. It has been truly an honor to work with Prof. Bhattacharya. I am also grateful to my committee memebers, Prof. Pei-Cheng Ku, Prof. Jamie Phillips, and Prof. Joanna Mirecki-Millunchick, for their time, insightful comments, and valuable suggestions. I would like to specially thank Prof. Millunchick for her valuable discussions and inputs during our collaborative endeavor. I am thankful to Dr. Meng Zhang and Dr. Wei Guo, my mentors in this group for getting me aquainted with epitaxial growth, fabrication and characterization. I would like to thank Dr. Junseok Heo for guiding me in my first research project here.
    [Show full text]
  • Solid State Laser
    SOLID STATE LASER Edited by Amin H. Al-Khursan Solid State Laser Edited by Amin H. Al-Khursan Published by InTech Janeza Trdine 9, 51000 Rijeka, Croatia Copyright © 2012 InTech All chapters are Open Access distributed under the Creative Commons Attribution 3.0 license, which allows users to download, copy and build upon published articles even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. After this work has been published by InTech, authors have the right to republish it, in whole or part, in any publication of which they are the author, and to make other personal use of the work. Any republication, referencing or personal use of the work must explicitly identify the original source. As for readers, this license allows users to download, copy and build upon published chapters even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. Notice Statements and opinions expressed in the chapters are these of the individual contributors and not necessarily those of the editors or publisher. No responsibility is accepted for the accuracy of information contained in the published chapters. The publisher assumes no responsibility for any damage or injury to persons or property arising out of the use of any materials, instructions, methods or ideas contained in the book. Publishing Process Manager Iva Simcic Technical Editor Teodora Smiljanic Cover Designer InTech Design Team First published February, 2012 Printed in Croatia A free online edition of this book is available at www.intechopen.com Additional hard copies can be obtained from [email protected] Solid State Laser, Edited by Amin H.
    [Show full text]
  • Impact of Dot Size on Dynamical Characteristics of Inas/Gaas Quantum Dot Lasers
    Impact of dot size on dynamical characteristics of InAs/GaAs quantum dot lasers Esfandiar Rajaei* and Mahdi Ahmadi Borji** Department of Physics, The University of Guilan, Namjoo Street, Rasht, Iran * Corresponding author, E-mail: [email protected], ** Email: [email protected] Abstract: The purpose of this research is to study laser dynamics of InAs/GaAs Quantum Dot Lasers (QDLs) by changing QD energy levels. To date, most of the investigations have focused on only one of these circumstances, and hardly the result of change in the energy levels can be seen in lasing. In this work, in the first step, energy levels of lens-shape QDs are investigated by the eight-band k.p method, their variation for different QD sizes are surveyed, and recombination energies of the discrete levels are determined. Then, by representing a three-level InAs/GaAs QD laser, dynamics of such a laser device is numerically studied by rate equations in which homogeneous and inhomogeneous broadenings are taken into account. The lasing process for both Ground State (GS) and Excited States (ES) was found to be much sensitive to the QD size. It was observed that in larger QDs, photon number and bandwidth of the small signal modulation decrease but turn-on delay, maximum output power, and threshold current of gain increase. It was also found that for a good modulation, smaller QDs, and form the point of view of high-power applications, larger QDs seem better. Keywords: quantum dot lasers, QD size, energy level control, small signal modulation I. INTRODUCTION Study of the structure of semiconductors enables to control their parameters such as energy gap, energy levels, band structures, etc; control of the basic factors of these structures results in high-performance devices.
    [Show full text]
  • Zhang Gsas.Harvard 0084L 10989.Pdf (11.58Mb)
    Manipulating Light on Wavelength Scale The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Zhang, Yinan. 2012. Manipulating Light on Wavelength Scale. Doctoral dissertation, Harvard University. Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:11051175 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA Manipulating Light on Wavelength Scale Y Z T S E A S D P E E H U C, M D © - Y Z A . esis advisor: Marko Loncar Yinan Zhang Manipulating Light on Wavelength Scale A Light, at the length-scale on the order of its wavelength, does not simply behave as “light ray”, but instead diffracts, scaers, and interferes with itself, as governed by Maxwell’s equations. A profound understanding of the underlying physics has inspired the emergence of a new frontier of materials and devices in the past few decades. is thesis explores the concepts and approaches for manipulating light at the wavelength-scale in a variety of topics, including anti-reective coatings, on- chip silicon photonics, optical microcavities and nanolasers, microwave particle accelerators, and optical nonlinearities. In Chapter , an optimal tapered prole that maximizes light transmission be- tween two media with different refractive indices is derived from analytical theory and numerical modeling. A broadband wide-angle anti-reective coating at the air/silicon interface is designed for the application of photovoltaics.
    [Show full text]
  • Front Cover CS V6mg.Indd 1 31/08/2017 16:10 Untitled-1 1 26/07/2017 09:21 Viewpoint by Dr Richard Stevenson, Editor
    Volume 23 Issue 6 August / September 2017 @compoundsemi www.compoundsemiconductor.net Lighting up silicon with InAs quantum dots MACOM Enabling breakthroughs in optical bandwidth density Novel cooling aid high-power laser diodes Easing the use of GaN power electronics An abundance of key elements for chipmakers Ultraviolet LEDs take aim at disinfection News Review, News Analysis, Features, Research Review, and much more... inside Free Weekly E News round up go to: www.compoundsemiconductor.net Front Cover CS v6MG.indd 1 31/08/2017 16:10 Untitled-1 1 26/07/2017 09:21 Viewpoint By Dr Richard Stevenson, Editor Telling our story POPULAR SCIENCES BOOKS aim to educate the layman. By better is to tell the story the way Johnstone does. It begins with eradicating equations, offering analogies and telling a story with a meeting of visionaries that plot out the rate of improvement a human touch, Joe Public can be entertained while learning in these devices, see where they are destined to go, and put the basics of a subject. plans in place to make this happen. Instrumental in the success is the backing by government, which uses its money very But that’s not the only benefi t of these books. They can be read effectively, alongside the introduction of standards that quash by experts, so that when they are at social gatherings and are the availability of inferior bulbs. asked what they do for a living, they can draw on what’s been written to give an answer that’s engaging and understandable. Read this book and you will also be able to wax lyrical about the benefi ts of LEDs in It is for that reason that I recommend Bob Johnstone’s new agriculture, and how the tuning of the book L.E.D.
    [Show full text]
  • Modified Droplet Epitaxy Gaas/Algaas Quantum Dots Grown
    Journal of Crystal Growth 253 (2003) 71–76 Modified droplet epitaxy GaAs/AlGaAs quantum dots grown on a variable thickness wetting layer S. Sanguinettia,b,*, K. Watanabeb, T. Tatenob, M. Guriolia,c, P. Wernerd, M. Wakakie, N. Koguchib a I.N.F.M. Dipartimento di Scienza dei Materiali, Universita" di Milano Bicocca, Via Cozzi 53, I-20125 Milano, Italy b National Institute for Materials Science, 1–2–1 Sengen, Tsukuba, Ibaraki 305–0047, Japan c L.E.N.S., Via Sansone 1, I-50019 Sesto Fiorentino, Italy d Max-Planck-Institut fur. Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany e Department of Electro-Photo Optics, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan Received 7 February 2003; accepted 14 February 2003 Communicated by M. Schieber Abstract We show that the use of modified droplet epitaxy allows to tune the wetting layer thickness in GaAs quantum dot structures. Morphological observations demonstrate that the wetting layer at the base of the dots can be controlled or even removed by changing the surface stoichiometry of substrates before droplet formations. Spectroscopical measurements show that the variation of the wetting layer thickness strongly influences the optical properties of the dots. The experimental transition energies of the dots well agree with a theoretical model based on effective mass approximation. r 2003 Elsevier Science B.V. All rights reserved. PACS: 78.67.Hc; 68.35.Fx Keywords: A3. Molecular beam epitaxy; A3. Quantum dots; B2. Semiconducting III–V materials 1. Introduction Stranski–Krastanov (SK) growth mode [4,5], has triggered an in-depth research of the physical The discovery of the self–organized growth of phenomena related to the QD growth.
    [Show full text]
  • Techniques for High-Speed Direct Modulation of Quantum Dot Lasers Yan Li
    University of New Mexico UNM Digital Repository Optical Science and Engineering ETDs Engineering ETDs 7-21-2008 Techniques for high-speed direct modulation of quantum dot lasers Yan Li Follow this and additional works at: https://digitalrepository.unm.edu/ose_etds Recommended Citation Li, Yan. "Techniques for high-speed direct modulation of quantum dot lasers." (2008). https://digitalrepository.unm.edu/ose_etds/ 17 This Dissertation is brought to you for free and open access by the Engineering ETDs at UNM Digital Repository. It has been accepted for inclusion in Optical Science and Engineering ETDs by an authorized administrator of UNM Digital Repository. For more information, please contact [email protected]. Yan Li Candidate Department of Electrical and Computer Engineering Department This dissertation is approved, and it is acceptable in quality and form for publication on microfilm: Approved by the Dissertation Committee: , Chairperson Accepted: Dean, Graduate School Date TECHNIQUES FOR HIGH-SPEED DIRECT MODULATION OF QUANTUM DOT LASERS BY YAN LI M.S. Optics, Sichuan University, 2000 DISSERTATION Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Optical Science and Engineering The University of New Mexico Albuquerque, New Mexico May, 2008 ACKNOWLEDGEMENTS My deepest gratitude is to my advisor, Prof. Luke F. Lester. I was fortunate to have his support to continue my research in the semiconductor laser area. His guidance, perspective and encouragement are always a major driving force for me to fulfill my dissertation and will benefit my future career. I really appreciate his infinite understanding and patience during the last four years. I also would like to thank Prof.
    [Show full text]
  • The Study of Coupling in Ingaas Quantum Rings Grown by Droplet Epitaxy
    The Study of Coupling in InGaAs Quantum Rings Grown by Droplet Epitaxy A thesis presented to the faculty of the College of Arts and Sciences of Ohio University In partial fulfillment of the requirements for the degree Master of Science Samar M. Alsolamy May 2013 © 2013 Samar M. Alsolamy. All Rights Reserved. 2 This thesis titled The Study of Coupling in InGaAs Quantum Rings Grown by Droplet Epitaxy by SAMAR M. ALSOLAMY has been approved for the Department of Physics and Astronomy and the College of Arts and Sciences by Eric A. Stinaff Associate Professor of Physics and Astronomy Robert Frank Dean, College of Arts and Sciences 3 ABSTRACT ALSOLAMY, SAMAR, M., M.S., May 2013, Physics and Astronomy The Study of Coupling in InGaAs Quantum Rings Grown by Droplet Epitaxy Director ofThesis: Eric A. Stinaff The use of metal droplet epitaxy may provide a novel method of growing laterally coupled nanostructures. We will present optical studies of InAs/GaAs nanostructures which result in twin quantum dots (QD) formed on a single quantum ring (QR). Previous studies have investigated the coupling between vertically grown quantum dot pairs. In this thesis, we have used photoluminescence (PL) and photoluminescence excitation (PLE) to examine the possibility of energy transfer and coupling between quantum dot pairs in a single InGaAs quantum ring grown by droplet epitaxy. Power dependent photoluminescence spectra reveal a few peaks at low power, which are identified with emission from the ground state of the individual dots. As the power is increased we observe multi-exciton and excited state emission. We then perform PLE, tuning the excitation laser energy continuously from the high energy ring emission down to the individual dot states.
    [Show full text]