LASER Light Amplification by Stimulated Emission of Radiation
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Book of Abstracts
Russian Academy of Sciences Institute of Problems of Chemical Physics RAS Joint Institute for High Temperatures RAS XIII International Conference on Physics of Non-Ideal Plasmas September 13 | 18, 2009, Chernogolovka, Russia Book of Abstracts Chernogolovka 2009 The book consists of the abstracts of oral and poster contributions to the XIII International Conference on Physics of Non-Ideal Plasmas (September 13 | 18, 2009, Chernogolovka, Russia). The Conference continues a tradi- tional series of meetings devoted to new theoretical and experimental results on the physics of dense non-ideal plasmas: Martzlow-Garwitz, 1980; Wus- trow, 1982; Biesenthal, 1984; Greifswald, 1986; Wustrow, 1988; Gosen, 1991; Markgrafenheide, 1993; Binz, 1995; Rostock, 1998; Greifswald, 2000; Valen- cia, 2003; Darmstadt, 2006. The following questions are covered: statistical physics and mathematical modeling (including simulation) of strongly cou- pled Coulomb systems, equilibrium properties and equation of state of dense plasmas, kinetics, transport and optical properties of dense Coulomb systems, dense hydrogen, laser and heavy-ion-produced plasmas, dense astrophysical plasmas, phase transitions in plasmas and fluids, dusty plasmas. The conference is held under financial support of the Russian Academy of Sciences, Russian Foundation for Basic Research (grant No. 09 { 02 { 06154Γ), and Dynasty Foundation. Contents 1 Statistical physics and mathematical modeling of strongly cou- pled Coulomb systems 16 1.1 Mathematical simulation of kinetic processes in the non-ideal nuclear-excited dust plasma of the noble gases Budnik A.P., Deputatova L.V., Fortov V.E., Kosarev V.A., Rykov V.A., Vladimirov V.I., JIHT RAS . 16 1.2 Diagnosics of dense plasmas via transport and optical proper- ties Reinholz H., Raitza T., R¨opke G., Wierling A., Winkel M., U. -
Micro-Cavity Fluidic Dye Lasers
Micro-Cavity Fluidic Dye Lasers M.Sc. Thesis Bjarne Helbo Student Number: c960336 Supervisors: Anders Kristensen and Aric Menon Mikroelektronik Centret (MIC) Technical University of Denmark (DTU) November 2002 Abstract i Abstract The work described in this masters thesis deals with development, fabrication, and optical characterization of micro-cavity fluidic dye lasers. The wide band fluorescence of organic dyes make them suitable as the active gain media for tunable dye lasers. Decreasing the laser cavity size down to the micron level makes dye lasers suitable for integration with existing bio/chemical microsystems. Theory for organic dyes is presented together with basic laser theory. The theory is used for explaining the behavior of the fabricated devices. Two types of micro-cavity fluidic dye laser devices were fabricated based on two dif- ferent micro-fabrication schemes. The devices were vertical emitting with fixed lasing wavelength. The initial device was a microfluidic channel defined with an KOH etch of silicon. The bottom (100) plane of the etched silicon channel was used as a deposition surface for a gold/chromium mirror. The etched surface was not smooth enough for mirror purpose and the following anodic bonding of a glass lid on the top made the surface even more rough. Due to thermal heating from the anodic bonding process the metals diffused into the silicon substrate and left the surface dull and rough, not suitable for optical mirrors. A cw argon ion laser (488 nm) was used for optical pumping of a Rhodamine 110 dye dissolved in ethanol, which was pumped through the microfluidic laser cavity. -
Joseph Weber's Contribution to Gravitational Waves and Neutrinos
Firenze University Press www.fupress.com/substantia Historical Article New Astronomical Observations: Joseph Weber’s Contribution to Gravitational Waves Citation: S. Gottardo (2017) New Astronomical Observations: Joseph and Neutrinos Detection Weber’s Contribution to Gravitational Waves and Neutrinos Detection. Sub- stantia 1(1): 61-67. doi: 10.13128/Sub- stantia-13 Stefano Gottardo Copyright: © 2017 S. Gottardo.This European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino (Flor- is an open access, peer-reviewed arti- ence), Italy cle published by Firenze University E-mail: [email protected] Press (http://www.fupress.com/substan- tia) and distribuited under distributed under the terms of the Creative Com- Abstract. Joseph Weber, form Maryland University, was a pioneer in the experimen- mons Attribution License, which per- tal research of gravitational waves and neutrinos. Today these two techniques are very mits unrestricted use, distribution, and promising for astronomical observation, since will allow to observe astrophysical phe- reproduction in any medium, provided nomena under a new light. We review here almost 30 years of Weber’s career spent the original author and source are on gravity waves and neutrinos; Weber’s experimental results were strongly criticized credited. by the international community, but his research, despite critics, boosted the brand Data Availability Statement: All rel- new (in mid-sixties of last century) research field of gravity waves to become one of evant data are within the paper and its the most important in XXI century. On neutrino side, he found an unorthodox way Supporting Information files. to reduce the size of detectors typically huge and he claimed to observe neutrinos flux with a small pure crystal of sapphire. -
Chapter 2 HISTORY and DEVELOPMENT of MILITARY LASERS
History and Development of Military Lasers Chapter 2 HISTORY AND DEVELOPMENT OF MILITARY LASERS JACK B. KELLER, JR* INTRODUCTION INVENTING THE LASER MILITARIZING THE LASER SEARCHING FOR HIGH-ENERGY LASER WEAPONS SEARCHING FOR LOW-ENERGY LASER WEAPONS RETURNING TO HIGHER ENERGIES SUMMARY *Lieutenant Colonel, US Army (Retired); formerly, Foreign Science Information Officer, US Army Medical Research Detachment-Walter Reed Army Institute of Research, 7965 Dave Erwin Drive, Brooks City-Base, Texas 78235 25 Biomedical Implications of Military Laser Exposure INTRODUCTION This chapter will examine the history of the laser, Military advantage is greatest when details are con- from theory to demonstration, for its impact upon the US cealed from real or potential adversaries (eg, through military. In the field of military science, there was early classification). Classification can remain in place long recognition that lasers can be visually and cutaneously after a program is aborted, if warranted to conceal hazardous to military personnel—hazards documented technological details or pathways not obvious or easily in detail elsewhere in this volume—and that such hazards deduced but that may be relevant to future develop- must be mitigated to ensure military personnel safety ments. Thus, many details regarding developmental and mission success. At odds with this recognition was military laser systems cannot be made public; their the desire to harness the laser’s potential application to a descriptions here are necessarily vague. wide spectrum of military tasks. This chapter focuses on Once fielded, system details usually, but not always, the history and development of laser systems that, when become public. Laser systems identified here represent used, necessitate highly specialized biomedical research various evolutionary states of the art in laser technol- as described throughout this volume. -
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. -
Part 2: Laser in Pulsed Operation
Part 2: Laser in pulsed operation 1 Theoretical principles 1.1 Generation of short laser pulses The output power of existing continuous wave laser systems is between a few milliwatts (He-Ne lasers) and a few hundred watts (Nd or CO2 lasers). However, there is a possibility to increase the output power of the laser for a small period of time by pulsed laser operation. Solid-state lasers are particularly suitable for this purpose, as they can achieve pulse peak output powers of up to 1012 W. This value corresponds approximately to the average electrical energy generation of the entire world. The difference, however, lies in the period in which this performance is achieved. While all the power plants together reach this value continuously, a single laser produces this high output power only for a duration of 10−13 s. In this case, the extremely short pulse duration appears to be disadvantageous, but there are also applications which exactly require this. One example is laser ablation, which is a method in material processing. Here, a small volume of material at the surface of a work piece can be evaporated if it is heated high enough in a very short amount of time. On the other hand, supplying the energy gradually would allow the heat to be absorbed into the bulk of the piece, never attaining a sufficiently high temperature above the evaporation point of the material. Other applications rely on the very high peak pulse power to obtain strong non-linear optical effects, like it is necessary for efficient second-harmonic generation or for optical parametric oscillators (OPO) which converts an input laser wave into two output waves of lower frequencies. -
Directed Energy Weapons—
Directed Energy Weapons— Are We There Yet? The Future of DEW Systems and Barriers to Success Elihu Zimet and Christopher Mann Center for Technology and National Security Policy National Defense University May 2009 The views expressed in this article are those of the authors and do not reflect the official policy or position of the National Defense University, the Department of Defense or the U.S. Government. All information and sources for this paper were drawn from unclassified materials. Elihu Zimet is a consultant to the Center for Technology and National Security Policy (CTNSP) at the National Defense University. Previously he was a Senior Research Fellow at the Potomac Institute for Policy Studies. Prior to that he headed the Expeditionary Warfare Science and Technology Department at the Office of Naval Research. In that position he directed science and technology (S&T) programs in missiles, directed energy, aircraft, and stealth as well as S&T support to the Marine Corps. Dr. Zimet holds a BS (ME) from the Polytechnic Institute of Brooklyn and a Ph.D. from Yale University. Christopher Mann is a Research Associate at CTNSP, National Defense University. He earned a M.A. in Security Policy Studies from the Elliott School of International Affairs and has served as the lead researcher on several New York Times best-selling books about national security. Defense & Technology Papers are published by the National Defense University Center for Technology and National Security Policy, Fort Lesley J. McNair, Washington, DC. CTNSP publications are available at http://www.ndu.edu/ctnsp/publications.html. ii Contents Introduction.................................................................................................................................... -
LIGO's Unsung Heroes : Nature News & Comment
NATURE | NEWS LIGO's unsung heroes Nature highlights just a few of the people who played a crucial part in the discovery of gravitational waves — but didn’t win the Nobel Prize. Davide Castelvecchi 09 October 2017 Corrected: 19 October 2017 Joe McNally/Getty LIGO hunts gravitational waves with the help of two laser interferometers — and hundreds of people. Expand Every October, the announcements of the Nobel Prizes bring with them some controversy. This year’s physics prize — in recognition of the Laser Interferometer Gravitational-Wave Observatory (LIGO) in the United States — was less debated than most. The three winners — Kip Thorne and Barry Barish, both at the California Institute of Technology (Caltech) in Pasadena, and Rainer Weiss at the Massachusetts Institute of Technology (MIT) in Cambridge — had attracted near-universal praise for their roles in the project’s success. But the award has still put into stark relief the difficulty of singling out just a few individuals from the large collaborations of today’s 'Big Science'. The LIGO collaboration uses two giant laser interferometers to listen for deformations in space-time caused by some of the Universe’s most cataclysmic events. Physicists detected their first gravitational waves — interpreted as being produced by the collision of two black holes more than a billion years ago — in September 2015. The resulting paper, published in February 20161, has a mind-boggling 1,004 authors. Some of those are members of the LIGO Laboratory, the Caltech–MIT consortium that manages LIGO’s two interferometers in Louisiana and Washington State. But the list also includes the larger LIGO Scientific Collaboration: researchers from 18 countries, some of which — such as Germany and the United Kingdom — have made crucial contributions to the detectors. -
A Laser (From the Acronym Light Amplification by Stimulated Emission of Radiation) Is an Optical Source That Emits Photons in a Coherent Beam
LASER A laser (from the acronym Light Amplification by Stimulated Emission of Radiation) is an optical source that emits photons in a coherent beam. The verb to lase means "to produce coherent light" or possibly "to cut or otherwise treat with coherent light", and is a back- formation of the term laser. Laser light is typically near-monochromatic, i.e. consisting of a single wavelength or color, and emitted in a narrow beam. This is in contrast to common light sources, such as the incandescent light bulb, which emit incoherent photons in almost all directions, usually over a wide spectrum of wavelengths. Laser action is explained by the theories of quantum mechanics and thermodynamics. Many materials have been found to have the required characteristics to form the laser gain medium needed to power a laser, and these have led to the invention of many types of lasers with different characteristics suitable for different applications. The laser was proposed as a variation of the maser principle in the late 1950's, and the first laser was demonstrated in 1960. Since that time, laser manufacturing has become a multi- billion dollar industry, and the laser has found applications in fields including science, industry, medicine, and consumer electronics. Contents [hide] 1 Physics 2 History 2.1 Recent innovations 3 Uses 3.1 Popular misconceptions 3.2 "LASER" 3.3 Scientific misconceptions 4 Laser safety 5 Categories 5.1 By type 5.2 By output power 6 See also 7 Further reading 7.1 Books 7.2 Periodicals 8 References 9 External links [edit] Physics See also: Laser science Principal components: 1. -
Amplified Spontaneous Emission Properties of Semiconducting Organic Materials
Int. J. Mol. Sci. 2010, 11, 2546-2565; doi:10.3390/ijms11062546 OPEN ACCESS International Journal of Molecular Sciences ISSN 1422-0067 http://www.mdpi.com/journal/ijms/ Review Amplified Spontaneous Emission Properties of Semiconducting Organic Materials Eva M. Calzado 1, Pedro G. Boj 2 and María A. Díaz-García 3,* 1 Departamento Física, Ingeniería de Sistemas y Teoría de la Señal and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, Alicante-03080, Spain; E-Mail: [email protected] 2 Departamento Óptica and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, Alicante-03080, Spain; E-Mail: [email protected] 3 Departamento Física Aplicada, Unidad asociada UA-CSIC and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, Alicante-03080, Spain * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +34-965903543; Fax: +34-965909726. Received: 7 May 2010 / Accepted: 10 June 2010 / Published: 18 June 2010 Abstract: This paper aims to review the recent advances achieved in the field of organic solid-state lasers with respect to the usage of semiconducting organic molecules and oligomers in the form of thin films as active laser media. We mainly focus on the work performed in the last few years by our research group. The amplified spontaneous emission (ASE) properties, by optical pump, of various types of molecules doped into polystyrene films in waveguide configuration, are described. The various systems investigated include N,N´-bis(3-methylphenyl)-N,N´-diphenylbenzidine (TPD), several perilenediimide derivatives (PDIs), as well as two oligo-phenylenevinylene derivatives. The ASE characteristics, i.e., threshold, emission wavelength, linewidth, and photostability are compared with that of other molecular materials investigated in the literature. -
A Brief History of Gravitational Waves
Review A Brief History of Gravitational Waves Jorge L. Cervantes-Cota 1, Salvador Galindo-Uribarri 1 and George F. Smoot 2,3,4,* 1 Department of Physics, National Institute for Nuclear Research, Km 36.5 Carretera Mexico-Toluca, Ocoyoacac, Mexico State C.P.52750, Mexico; [email protected] (J.L.C.-C.); [email protected] (S.G.-U.) 2 Helmut and Ana Pao Sohmen Professor at Large, Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, 999077 Kowloon, Hong Kong, China. 3 Université Sorbonne Paris Cité, Laboratoire APC-PCCP, Université Paris Diderot, 10 rue Alice Domon et Leonie Duquet 75205 Paris Cedex 13, France. 4 Department of Physics and LBNL, University of California; MS Bldg 50-5505 LBNL, 1 Cyclotron Road Berkeley, CA 94720, USA. * Correspondence: [email protected]; Tel.:+1-510-486-5505 Abstract: This review describes the discovery of gravitational waves. We recount the journey of predicting and finding those waves, since its beginning in the early twentieth century, their prediction by Einstein in 1916, theoretical and experimental blunders, efforts towards their detection, and finally the subsequent successful discovery. Keywords: gravitational waves; General Relativity; LIGO; Einstein; strong-field gravity; binary black holes 1. Introduction Einstein’s General Theory of Relativity, published in November 1915, led to the prediction of the existence of gravitational waves that would be so faint and their interaction with matter so weak that Einstein himself wondered if they could ever be discovered. Even if they were detectable, Einstein also wondered if they would ever be useful enough for use in science. -
The Search for the Gentle Tremble
Flashback_Gravitational Waves The Search for the Gentle Tremble Gravitational waves are some of the most spectacular predictions of the 1915 general theory of relativity. However, it wasn’t until half a century later that physicist Joseph Weber attempted to track them down. In the early 1970s, Max Planck scientists also began working in this research field, and developed second-generation detectors. The groundwork laid by these pioneers meant the waves in space-time ceased to be just figments of the imagination: in September 2015 they were finally detected. TEXT HELMUT HORNUNG Albert Einstein is beset by doubt: it will never be possible to de- of relativity ultimately benefits gravitational waves, too, which tect gravitational waves – the tremble in space-time is simply too strike a chord with at least one physicist: Joseph Weber. weak! Yet it was he himself who had postulated their existence, Born in 1919 in New Jersey, the researcher at the University of which follows from the general theory of relativity he put forward Maryland has an idea for a simple experiment: he suspends an in- in November 1915. A short time later, in 1916 and again in 1918, he credibly heavy aluminum cylinder – 1.5 meters long and 60 centi- devotes a paper to this phenomenon. meters across – in a steel wire loop and attaches piezo sensors to Two decades later, he suddenly has a change of heart: “I have its middle to register oscillations. The whole test rig is housed in been working with a young colleague [Nathan Rosen] and we have a vacuum chamber.