Part 2: Laser in Pulsed Operation
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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. -
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. -
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. -
Practical Tips for Two-Photon Microscopy
Appendix 1 Practical Tips for Two-Photon Microscopy Mark B. Cannell, Angus McMorland, and Christian Soeller INTRODUCTION blue and green diode lasers. To provide an alignment beam to which the external laser can be aligned, light from this reference As is clear from a number of the chapters in this volume, 2-photon laser needs to be bounced back through the microscope optical microscopy offers many advantages, especially for living-cell train and out through the external coupling port: studies of thick specimens such as brain slices and embryos. CAUTION: Before you switch on the reference laser in this However, these advantages must be balanced against the fact that configuration make sure that all PMTs are protected and/or commercial multiphoton instrumentation is much more costly than turned off. the equipment used for confocal or widefield/deconvolution. Given Place a front-surface mirror on the stage of the microscope and these two facts, it is not surprising that, to an extent much greater focus onto the reflective surface using an air objective for conve- than is true of confocal, many researchers have decided to add a nience (at sharp focus, you should be able to see scratches or other femtosecond (fs) pulsed near-IR laser to a scanner and a micro- mirror defects through the eyepieces). The idea of this method is scope to make their own system (Soeller and Cannell, 1996; Tsai to cause the reference laser beam to bounce back through the et al., 2002; Potter, 2005). Even those who purchase a commercial optical train and emerge from the other laser port. -
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. -
CW Ndryag LASER Martin David Dawson, B.Sc
CHARACTERISATION AND APPLICATION OF A MODE-LOCKED (MODE-LOCKED/Q-SWITCHED) C.W. NdrYAG LASER Martin David Dawson, B.Sc., A.R.C.S. A Thesis submitted for the degree of Doctor of Philosophy of the University of London and for the Diploma of Membership of Imperial College Optics Group Blackett Laboratory Imperial College of Science and Technology M a r c h 1985 London SW7 2BZ DEDICATION To Mam, Dad and Pam ABSTRACT A synchronously operated (Synchroscan) picosecond streak camera has been used in a direct time-resolved study of laser emission from a GaAs/(GaAl)As double heterostructure laser pumped by 514-nm Ar ion laser pulses of duration close to the ^ 60ps Fourier-transform limit. Semiconductor laser pulsewidths as short as 20ps were recorded and the dependence of the temporal characteristics of these pulses on average pump power was investigated. Optical pulses of similar wavelength (532nm) to those obtained from the Ar ion laser, but having considerably shorter duration (^30ps), have been generated by frequency doubling the output of a mode-locked continuous wave (c.w.) Nd:YAG laser using Type II phase matching in a KTiOPOi* (K.T.P.) crystal. High doubling efficiencies (a.10/6 average power conversion) were achieved. These pulses have been used to synchronously pump a Rhodamine 6G jet-stream dye laser, whose performance is compared to its Ar ion 514nm-pumped counterpart. The mode-locked c.w. Nd:YAG laser itself has been thoroughly characterised and various changes made to improve the short and long term stability of the output. Simultaneous Q-switching of this laser at repetition rates ^ 1kHz, both with and without prelasing, has been investigated in detail using streak cameras. -
Two-Photon-Excited Fluorescence (TPEF) and Fluorescence Lifetime Imaging (FLIM) with Sub-Nanosecond Pulses and a High Analog Bandwidth Signal Detection
Two-photon-excited fluorescence (TPEF) and fluorescence lifetime imaging (FLIM) with sub-nanosecond pulses and a high analog bandwidth signal detection Matthias Eibl1, Sebastian Karpf2, Hubertus Hakert1, Daniel Weng1, and Robert Huber1 1Institut für Biomedizinische Optik, Universität zu Lübeck, Lübeck, Peter-Monnik-Weg 4, 23562 Lübeck, Germany 2Department of Electrical Engineering, University of California, Los Angeles, California 90095, USA ABSTRACT Two-photon excited fluorescence (TPEF) microscopy and fluorescence lifetime imaging (FLIM) are powerful imaging techniques in bio-molecular science. The need for elaborate light sources for TPEF and speed limitations for FLIM, however, hinder an even wider application. We present a way to overcome this limitations by combining a robust and inexpensive fiber laser for nonlinear excitation with a fast analog digitization method for rapid FLIM imaging. The applied sub nanosecond pulsed laser source is synchronized to a high analog bandwidth signal detection for single shot TPEF- and single shot FLIM imaging. The actively modulated pulses at 1064nm from the fiber laser are adjustable from 50ps to 5ns with kW of peak power. At a typically applied pulse lengths and repetition rates, the duty cycle is comparable to typically used femtosecond pulses and thus the peak power is also comparable at same cw-power. Hence, both types of excitation should yield the same number of fluorescence photons per time on average when used for TPEF imaging. However, in the 100ps configuration, a thousand times more fluorescence photons are generated per pulse. In this paper, we now show that the higher number of fluorescence photons per pulse combined with a high analog bandwidth detection makes it possible to not only use a single pulse per pixel for TPEF imaging but also to resolve the exponential time decay for FLIM. -
Time-Resolved Studies of Nd:YAG Loser-Induced Breakdown
Time-Resolved Studies of Nd:YAG Loser-Induced Breakdown Plasma Formation, Acoustic Wave Generation, and Cavitation Jomes G. Fujimoro,* Wei Z. Liaf Erich P. Ippen,* Carmen A. PuliQfiro4 and Roger F. Sreinerr^: The use of high intensity ultrashort pulsed laser radiation to produce optical breakdown is an important approach for the surgical treatment of intraocular structures. We have investigated the transient properties of Nd:YAG laser induced breakdown in a saline model using time-resolved spectroscopic techniques. Spatially resolved pump and probe techniques are applied to study the dynamic behavior of the plasma formation, acoustic wave generation, and cavitation processes which accompany the optical breakdown. Measurements of plasma shielding and luminescence indicate that the laser induced plasma forms on a subnanosecond time scale and has a lifetime of several nanoseconds. An acoustic transient is generated at the breakdown site and propagates spherically outward with an initial hypersonic velocity, then loses energy and propagates at sound velocity. Transient heating following the plasma formation produces a liquid-gas phase change and gives rise to cavitation or gas bubble formation. This gas bubble expands rapidly for several microseconds, then slows to reach its maximum size and finally collapses. Invest Ophthalmol Vis Sci 26:1771-1777, 1985 Short pulsed Q-switched and modelocked Nd:YAG important role in protecting the retina from the inci- lasers have recently achieved widespread use in dent laser energy,10"12'25"28 while the -
LASER Light Amplification by Stimulated Emission of Radiation
LASER Light Amplification by Stimulated Emission of Radiation Principle and applications The process which makes lasers possible, Stimulated Emission, was proposed in 1917 by Albert Einstein. No one realized the incredible potential of this concept until the 1950's, when practical research was first performed on applying the theory of stimulated emission to making lasers. It wasn't until 1960 that the first true laser was made by Theodore Maimam, out of synthetic ruby. Many ideas for laser applications quickly followed, including some that never worked, like the laser eraser. Still, the early pioneers of laser technology would be shocked and amazed to see the multitude of ways that lasers are used by everyone, everyday, in today's worlds Ordinary light laser light :- 1. directional 2. coherent 3. high intensity 4. Monochromatic Properties of LASER light • Monochromaticity: Properties of LASER light • Directionality: Conventional light source Beam Divergence angle (θd) • Highly Intense: since highly directional, coherent entire output is concentrated in a small region and intensity becomes very high I = (10/ λ)2 P P= power radiated by laser Properties of LASER light Incoherent light waves coherent light waves Laser History • Was based on Einstein’s idea of the “particlewave duality” of light, more than 30 years earlier • Invented in 1958 by Charles Townes (Nobel prize in Physics 1964) and Arthur Schawlow of Bell Laboratories • The first patent (1958) MASER = Microwave Amplification by Stimulated Emission of Radiation • 1958: Schawlow, A.L. and Townes, C.H. – Proposed the realization of masers for light and infrared got Nobel prize 1917: Einstein, A. - Concept and theory of stimulated light emission 1948: Gabor, D. -
Module 1-1 Elements and Operation of a Laser
1 MODULE 1-1 ELEMENTS AND OPERATION OF A LASER 2 (1) The laser is a light source that exhibits unique properties and a wide variety of applications. Lasers are used in welding, surveying, medicine, communication, national defense, and as tools in many areas of scientific research. Many types of lasers are commercially available today, ranging in size from devices that can rest on a fingertip to those that fill large buildings. All these lasers have certain basic characteristic properties in common. (2) This module discusses the basic properties that distinguish laser light from other light sources and the essential elements required to produce this unique light. The lasing process is examined briefly, and several of the terms used to describe and characterize the process are introduced. In the laboratory section, the student will become acquainted with the basic safety procedures for the operation of a low-powered helium-neon gas laser and will identify the components of that laser. (3)The student should take particular note that this module is designed to introduce all of the concepts to be studied in this course. Each topic covered here is discussed in greater detail in later modules. Upon completion of this module, the student should be able to: 1.1 Define the following properties of laser light: o 1.1.1 Monochromaticity. o 1.1.2 Directionality. o 1.1.3 Coherence. 1.2 Define the following terms that relate to the lasing process: o 1.2.1 Photon. o 1.2.2 Wavelength. o 1.2.3 Atomic ground state.