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An Application of the Theory of Laser to Nitrogen Laser Pumped Dye Laser
SD9900039 AN APPLICATION OF THE THEORY OF LASER TO NITROGEN LASER PUMPED DYE LASER FATIMA AHMED OSMAN A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Physics. UNIVERSITY OF KHARTOUM FACULTY OF SCIENCE DEPARTMENT OF PHYSICS MARCH 1998 \ 3 0-44 In this thesis we gave a general discussion on lasers, reviewing some of are properties, types and applications. We also conducted an experiment where we obtained a dye laser pumped by nitrogen laser with a wave length of 337.1 nm and a power of 5 Mw. It was noticed that the produced radiation possesses ^ characteristic^ different from those of other types of laser. This' characteristics determine^ the tunability i.e. the possibility of choosing the appropriately required wave-length of radiation for various applications. DEDICATION TO MY BELOVED PARENTS AND MY SISTER NADI A ACKNOWLEDGEMENTS I would like to express my deep gratitude to my supervisor Dr. AH El Tahir Sharaf El-Din, for his continuous support and guidance. I am also grateful to Dr. Maui Hammed Shaded, for encouragement, and advice in using the computer. Thanks also go to Ustaz Akram Yousif Ibrahim for helping me while conducting the experimental part of the thesis, and to Ustaz Abaker Ali Abdalla, for advising me in several respects. I also thank my teachers in the Physics Department, of the Faculty of Science, University of Khartoum and my colleagues and co- workers at laser laboratory whose support and encouragement me created the right atmosphere of research for me. Finally I would like to thank my brother Salah Ahmed Osman, Mr. -
Population Inversion X-Ray Laser Oscillator
Population inversion X-ray laser oscillator Aliaksei Halavanaua, Andrei Benediktovitchb, Alberto A. Lutmanc , Daniel DePonted, Daniele Coccoe , Nina Rohringerb,f, Uwe Bergmanng , and Claudio Pellegrinia,1 aAccelerator Research Division, SLAC National Accelerator Laboratory, Menlo Park, CA 94025; bCenter for Free Electron Laser Science, Deutsches Elektronen-Synchrotron, Hamburg 22607, Germany; cLinac & FEL division, SLAC National Accelerator Laboratory, Menlo Park, CA 94025; dLinac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA 94025; eLawrence Berkeley National Laboratory, Berkeley, CA 94720; fDepartment of Physics, Universitat¨ Hamburg, Hamburg 20355, Germany; and gStanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 Contributed by Claudio Pellegrini, May 13, 2020 (sent for review March 23, 2020; reviewed by Roger Falcone and Szymon Suckewer) Oscillators are at the heart of optical lasers, providing stable, X-ray free-electron lasers (XFELs), first proposed in 1992 transform-limited pulses. Until now, laser oscillators have been (8, 9) and developed from the late 1990s to today (10), are a rev- available only in the infrared to visible and near-ultraviolet (UV) olutionary tool to explore matter at the atomic length and time spectral region. In this paper, we present a study of an oscilla- scale, with high peak power, transverse coherence, femtosecond tor operating in the 5- to 12-keV photon-energy range. We show pulse duration, and nanometer to angstrom wavelength range, that, using the Kα1 line of transition metal compounds as the but with limited longitudinal coherence and a photon energy gain medium, an X-ray free-electron laser as a periodic pump, and spread of the order of 0.1% (11). -
Optical Pumping of Stored Atomic Ions (*)
Ann. Phys. Fr. 10 (1985) 737-748 DhCEMBRE 1985, PAGE 131 Optical pumping of stored atomic ions (*) D. J. Wineland, W. M. Itano, J. C. Bergquist, J. J. Bollinger and J. D. Prestage Time and Frequency Division, National Bureau of Standards, Boulder, Colorado 80303, U.S.A. Resume. - Ce texte discute les expkriences de pompage optique sur des ions atomiques confints dans des pikges tlectromagnttiques. Du fait de la faible relaxation et des dtplacements d'energie trbs petits des ions confine$ on peut obtenir une trb haute rtsolution et une tres grande prkision dans les exptriences de pompage optique associt a la double rtsonance. Dans la ligne de l'idee de Kastler de (( lumino-rtfrigtration H (1950), l'tnergie cinttique des niveaux des ions confines peut Ctre pompke optiquement. Cette technique, appelee refroidissement laser, rtduit sensiblement les dtplacements de frtquence Doppler dans les spectres. Abstract. - Optical pumping experiments on atomic ions which are stored in ekG tromagnetic (( traps )) are discussed. Weak relaxation and extremely small energy shifts of the stored ions lead to very high resolution and accuracy in optical pumping- double resonance experiments. In the same spirit of Kastler's proposal for (( lumino refrigeration )) (1950), the kinetic energy levels of stored ions can be optically pumped. This technique, which has been called laser cooling significantly reduces Doppler frequency shifts in the spectra. 1. Introduction. For more than thirty years, the technique of optical pumping, as originally proposed by Alfred Kastler [I], has provided information about atomic structure, atom-atom interactions, and the interaction of atoms with external radiation. This technique continues today as one of the primary methods used in atomic physics. -
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. -
Construction of a Flashlamp-Pumped Dye Laser and an Acousto-Optic
; UNITED STATES APARTMENT OF COMMERCE oUBLICATION NBS TECHNICAL NOTE 603 / v \ f ''ttis oi Construction of a Flashlamp-Pumped Dye Laser U.S. EPARTMENT OF COMMERCE and an Acousto-Optic Modulator National Bureau of for Mode-Locking Iandards — NATIONAL BUREAU OF STANDARDS 1 The National Bureau of Standards was established by an act of Congress March 3, 1901. The Bureau's overall goal is to strengthen and advance the Nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the Nation's physical measure- ment system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau consists of the Institute for Basic Standards, the Institute for Materials Research, the Institute for Applied Technology, the Center for Computer Sciences and Technology, and the Office for Information Programs. THE INSTITUTE FOR BASIC STANDARDS provides the central basis within the United States of a complete and consistent system of physical measurement; coordinates that system with measurement systems of other nations; and furnishes essential services leading to accurate and uniform physical measurements throughout the Nation's scien- tific community, industry, and commerce. The Institute consists of a Center for Radia- tion Research, an Office of Measurement Services and the following divisions: Applied Mathematics—Electricity—Heat—Mechanics—Optical Physics—Linac Radiation 2—Nuclear Radiation 2—Applied Radiation 2—Quantum Electronics 3— Electromagnetics 3—Time and Frequency 3 —Laboratory Astrophysics3—Cryo- 3 genics . -
Gaussian Beams • Diffraction at Cavity Mirrors Creates Gaussian Spherical
Gaussian Beams • Diffraction at cavity mirrors creates Gaussian Spherical Waves • Recall E field for Gaussian U ⎛ ⎡ x2 + y2 ⎤⎞ 0 ⎜ ( ) ⎟ u( x,y,R,t ) = exp⎜i⎢ω t − Kr − ⎥⎟ R ⎝ ⎣ 2R ⎦⎠ • R becomes the radius of curvature of the wave front • These are really TEM00 mode emissions from laser • Creates a Gaussian shaped beam intensity ⎛ − 2r 2 ⎞ 2P ⎛ − 2r 2 ⎞ I( r ) I exp⎜ ⎟ exp⎜ ⎟ = 0 ⎜ 2 ⎟ = 2 ⎜ 2 ⎟ ⎝ w ⎠ π w ⎝ w ⎠ Where P = total power in the beam w = 1/e2 beam radius • w changes with distance z along the beam ie. w(z) Measurements of Spotsize • For Gaussian beam important factor is the “spotsize” • Beam spotsize is measured in 3 possible ways • 1/e radius of beam • 1/e2 radius = w(z) of the radiance (light intensity) most common laser specification value 13% of peak power point point where emag field down by 1/e • Full Width Half Maximum (FWHM) point where the laser power falls to half its initial value good for many interactions with materials • useful relationship FWHM = 1.665r1 e FWHM = 1.177w = 1.177r 1 e2 w = r 1 = 0.849 FWHM e2 Gaussian Beam Changes with Distance • The Gaussian beam radius of curvature with distance 2 ⎡ ⎛π w2 ⎞ ⎤ R( z ) = z⎢1 + ⎜ 0 ⎟ ⎥ ⎜ λz ⎟ ⎣⎢ ⎝ ⎠ ⎦⎥ • Gaussian spot size with distance 1 2 2 ⎡ ⎛ λ z ⎞ ⎤ w( z ) = w ⎢1 + ⎜ ⎟ ⎥ 0 ⎜π w2 ⎟ ⎣⎢ ⎝ 0 ⎠ ⎦⎥ • Note: for lens systems lens diameter must be 3w0.= 99% of power • Note: some books define w0 as the full width rather than half width • As z becomes large relative to the beam asymptotically approaches ⎛ λ z ⎞ λ z w(z) ≈ w ⎜ ⎟ = 0 ⎜ 2 ⎟ ⎝π w0 ⎠ π w0 • Asymptotically light -
Rate Equations
Ultrafast Optical Physics II (SoSe 2019) Lecture 4, May 3, 2019 (1) Laser rate equations (2) Laser CW operation: stability and relaxation oscillation (3) Q-switching: active and passive 1 Possible laser cavity configurations The laser (oscillator) concept explained using a circuit model. 2 Self-consistent in steady state V.A. Lopota and H. Weber, fundamentals of the semiclassical laser theory 3 Laser rate equations Interaction cross section: [Unit: cm2] !") ") Spontaneous = −*") = − !$ τ21 emission § Interaction cross section is the probability that an interaction will occur between EM !" field and the atomic system. # = −'" ( !$ # § Interaction cross section only depends Absorption on the dipole matrix element and the linewidth of the transition !" ) Stimulated = −'")( !$ emission 4 How to achieve population inversion? relaxation relaxation rate relaxation Induced transitions Pumping rate relaxation Pumping by rate absorption relaxation relaxation rate Four-level gain medium 5 Laser rate equations for three-level laser medium If the relaxation rate is much faster than and the number of possible stimulated emission events that can occur , we can set N1 = 0 and obtain only a rate equation for the upper laser level: This equation is identical to the equation for the inversion of the two-level system: upper level lifetime equilibrium upper due to radiative and level population w/o non-radiative photons present processes 6 More on laser rate equations Laser gain material V:= Aeff L Mode volume fL: laser frequency I: Intensity vg: group velocity -
Improved Laser Based Photoluminescence on Single-Walled Carbon Nanotubes
Improved laser based photoluminescence on single-walled carbon nanotubes S. Kollarics,1 J. Palot´as,1 A. Bojtor,1 B. G. M´arkus,1 P. Rohringer,2 T. Pichler,2 and F. Simon1 1Department of Physics, Budapest University of Technology and Economics and MTA-BME Lend¨uletSpintronics Research Group (PROSPIN), P.O. Box 91, H-1521 Budapest, Hungary 2Faculty of Physics, University of Vienna, Strudlhofgasse 4., Vienna A-1090, Austria Photoluminescence (PL) has become a common tool to characterize various properties of single- walled carbon nanotube (SWCNT) chirality distribution and the level of tube individualization in SWCNT samples. Most PL studies employ conventional lamp light sources whose spectral dis- tribution is filtered with a monochromator but this results in a still impure spectrum with a low spectral intensity. Tunable dye lasers offer a tunable light source which cover the desired excitation wavelength range with a high spectral intensity, but their operation is often cumbersome. Here, we present the design and properties of an improved dye-laser system which is based on a Q-switch pump laser. The high peak power of the pump provides an essentially threshold-free lasing of the dye laser which substantially improves the operability. It allows operation with laser dyes such as Rhodamin 110 and Pyridin 1, which are otherwise on the border of operation of our laser. Our sys- tem allows to cover the 540-730 nm wavelength range with 4 dyes. In addition, the dye laser output pulses closely follow the properties of the pump this it directly provides a time resolved and tunable laser source. -
High Performance Flash and Arc Lamps Catalog
Europe: Saxon Way, Bar Hill, Cambridge, CB3 8SL Tel: +44 (0)1954 782266 Fax: +44 (0)1954 782993 USA: 44370 Christy St., Freemont, CA 94538, USA Tel: (800) 775-OPTO Tel: (510) 979-6500 Fax: (510) 687-1344 USA: 35 Congress Street, Salem, MA 01970, USA Tel: (978) 745-3200 Fax: (978) 745-0894 Asia: 47 Ayer Rajah Cresent, 06-12, Singapore 139947 Tel: +65-775-2022 Fax: +65-775-1008 Japan: 18F, Parale Mitsui Building 8, Higashida-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa-ken, 210-0005 Japan Tel: 81 44 200 9150 Fax: 81 44 200 9160 www.perkinelmer.com/opto Optoelectronics Lighting Imaging Telecom High Performance Flash and Arc Lamps Lighting Imaging Teleco m Introduction This publication is divided into two sections: Past, Present and Future Part 1 – Technical Information Solid state laser systems have historically used pulsed and CW (DC) xenon or krypton filled arc lamps as exci- Part 2 – Product Range tation for pump sources. When in 1960, at Hughes Research Labs, the first practical pulsed laser system Part 1 is intended to give the necessary technical infor- was demonstrated by mation to manufacturers, designers and researchers to T. H. Maiman the technology and understanding enable them to select the correct flashlamp for their involved in the manufacture and operation of application and also to give an insight into the design flashlamps was of a very basic nature. Up to procedures necessary for correct flashlamp operation. that time (1960) the major use of flashlamps was pho- Part 2 is a guide to the wide, varied and complex range tography and related applications. -
Imaging with Second-Harmonic Generation Nanoparticles
1 Imaging with Second-Harmonic Generation Nanoparticles Thesis by Chia-Lung Hsieh In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy California Institute of Technology Pasadena, California 2011 (Defended March 16, 2011) ii © 2011 Chia-Lung Hsieh All Rights Reserved iii Publications contained within this thesis: 1. C. L. Hsieh, R. Grange, Y. Pu, and D. Psaltis, "Three-dimensional harmonic holographic microcopy using nanoparticles as probes for cell imaging," Opt. Express 17, 2880–2891 (2009). 2. C. L. Hsieh, R. Grange, Y. Pu, and D. Psaltis, "Bioconjugation of barium titanate nanocrystals with immunoglobulin G antibody for second harmonic radiation imaging probes," Biomaterials 31, 2272–2277 (2010). 3. C. L. Hsieh, Y. Pu, R. Grange, and D. Psaltis, "Second harmonic generation from nanocrystals under linearly and circularly polarized excitations," Opt. Express 18, 11917–11932 (2010). 4. C. L. Hsieh, Y. Pu, R. Grange, and D. Psaltis, "Digital phase conjugation of second harmonic radiation emitted by nanoparticles in turbid media," Opt. Express 18, 12283–12290 (2010). 5. C. L. Hsieh, Y. Pu, R. Grange, G. Laporte, and D. Psaltis, "Imaging through turbid layers by scanning the phase conjugated second harmonic radiation from a nanoparticle," Opt. Express 18, 20723–20731 (2010). iv Acknowledgements During my five-year Ph.D. studies, I have thought a lot about science and life, but I have never thought of the moment of writing the acknowledgements of my thesis. At this moment, after finishing writing six chapters of my thesis, I realize the acknowledgment is probably one of the most difficult parts for me to complete. -
Terahertz Sources
Terahertz sources Pavel Shumyatsky Robert R. Alfano Downloaded from SPIE Digital Library on 22 Mar 2011 to 128.59.62.83. Terms of Use: http://spiedl.org/terms Journal of Biomedical Optics 16(3), 033001 (March 2011) Terahertz sources Pavel Shumyatsky and Robert R. Alfano City College of New York, Institute for Ultrafast Spectroscopy and Lasers, Physics Department, MR419, 160 Convent Avenue, New York, New York 10031 Abstract. We present an overview and history of terahertz (THz) sources for readers of the biomedical and optical community for applications in physics, biology, chemistry, medicine, imaging, and spectroscopy. THz low-frequency vibrational modes are involved in many biological, chemical, and solid state physical processes. C 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.3554742] Keywords: terahertz sources; time domain terahertz spectroscopy; pumps; probes. Paper 10449VRR received Aug. 10, 2010; revised manuscript received Jan. 19, 2011; accepted for publication Jan. 25, 2011; published online Mar. 22, 2011. 1 Introduction Yajima et al.4 first reported on tunable far-infrared radiation by One of the most exciting areas today to explore scientific and optical difference-frequency mixing in nonlinear crystals. These engineering phenomena lies in the terahertz (THz) spectral re- works have laid the foundation and were used for a decade and gion. THz radiation are electromagnetic waves situated between initiated the difference-frequency generation (DFG), parametric the infrared and microwave regions of the spectrum. The THz amplification, and optical rectification methods. frequency range is defined as the region from 0.1 to 30 THz. The The THz region became more attractive for investigation active investigations of the terahertz spectral region did not start owing to the appearance of new methods for generating T-rays until two decades ago with the advent of ultrafast femtosecond based on picosecond and femtosecond laser pulses. -
A Fundamental Approach to Phase Noise Reduction in Hybrid Si/III-V Lasers
A fundamental approach to phase noise reduction in hybrid Si/III-V lasers Thesis by Scott Tiedeman Steger In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy California Institute of Technology Pasadena, California 2014 (Defended May 14, 2014) ii © 2014 Scott Tiedeman Steger All Rights Reserved iii Contents Acknowledgements ix Abstract xi 1 Introduction1 1.1 Narrow-linewidth laser sources in coherent communication......1 1.2 Low phase noise Si/III-V lasers.....................4 2 Phase noise in laser fields7 2.1 Optical cavities..............................8 2.1.1 Loss................................8 2.1.2 Gain................................9 2.1.3 Quality factor........................... 10 2.1.4 Threshold condition....................... 11 2.2 Interaction of carriers with cavity modes................ 11 2.2.1 Spontaneous transitions into the lasing mode.......... 12 2.2.2 Spontaneous transitions into all modes............. 17 2.2.3 The spontaneous emission coupling factor........... 19 2.2.4 Stimulated transitions...................... 19 2.3 A phenomenological calculation of spontaneous emission into a lasing mode above threshold........................... 21 2.3.1 Number of carriers........................ 21 2.3.2 Total spontaneous emission rate................. 21 2.4 Phasor description of phase noise in a laser............... 23 iv 2.4.1 Spontaneous photon generation................. 25 2.4.2 Photon storage.......................... 27 2.4.3 Spectral linewidth of the optical field.............. 29 2.4.4 Phase noise power spectral density............... 30 2.4.5 Linewidth enhancement factor.................. 32 2.4.6 Total linewidth.......................... 34 3 Phase noise in hybrid Si/III-V lasers 35 3.1 The advantages of hybrid Si/III-V...................