Modern optics Lasers
|
|
- Vivien McCormick
- 5 years ago
- Views:
Transcription
1 Chapter 13 Phys 322 Lecture 36 Modern optics Lasers Reminder: Please complete the online course evaluation Last lecture: Review discussion (no quiz)
2 LASER = Light Amplification by Stimulated Emission of Radiation Laser is a device which transforms energy from other forms into (coherent and highly directional) electromagnetic radiation. Chemical energy Electron beam Electric current Electromagnetic radiation 1917 A. Einstein postulates photons and stimulated emission 1954 First microwave laser (MASER), Townes, Shawlow, Prokhorov 1960 First optical laser (Maiman) 1964 Nobel Prize in Physics: Townes, Prokhorov, Basov
3 Laser System 1. Active (gain) medium that can amplify light that passes through it 2. Energy pump source to create a population inversion in the gain medium 3. Two mirrors that form a resonator cavity
4 Gain spectrum can be very broad
5 Broadening of the gain spectrum
6 Laser Cavity
7 Laser Cavity Longitudinal cavity modes
8 Longitudinal modes in Fabry-Perot cavity
9
10 Transverse modes
11 Challenge: How to make a laser operate in a single basic transverse mode?
12 Laser radiation - properties Monochromaticity Directionality Coherence
13 Monochromaticity
14 Directionality Radiation comes out of the laser in a certain direction, and spreads at a defined divergence angle () This angular spreading of a laser beam is generally very small compared to other sources of electromagnetic radiation, and described by a small divergence angle I W ~ 0.1mW/cm 2 R Lamp: W = 100 W, 2 at L = 2 m He-Ne Laser: W = 1 mw, r = 2 mm, R = r + L /2 = 2.1 mm, I = 8 mw/cm 2 = 0.1 mrad
15 Fraunhofer diffraction of a laser beam A laser beam typically has a Gaussian radial profile: Ex (, y) exp No aperture is involved. x y w0 What will its electric field be far away?, Y E( x, y) E k k x Ex (, y ) exp y In terms of x 1 and y 1 : k z w 2 0 x where: 2w 0 k Ek ( x, ky) exp The Fourier transform of a Gaussian is a Gaussian. k 2 2 x y y x 4 or Ex (, y) exp 2z z w1 kw w 0 0 z 4 2w 1 w 2 0 y w1
16 Angular divergence of a laser beam The beam diverges. What will its divergence angle be? 2w 0 w 1 Recall that: w 1 z w 0 z The half-angle will be: w tan( ) z 1 z/ w z 0 The divergence half-angle will be: w 0
17 Laser radiation - properties Monochromaticity Directionality Coherence
18 Coherence E A i cos( t ) i i Laser radiation is composed of waves at the same wavelength, which start at the same time and keep their relative phase as they advance.
19 Coherence review Conditions for interference 1) For producing stable pattern, the two sources must have nearly the same frequency. 2) For clear pattern, the two sources must have similar amplitude. 3) For producing interference pattern, coherent sources are required. Temporal coherence: Time interval in which the light resembles a sinusoidal wave. (~10 ns for natural light) Longitudinal coherence length: l c = ct c. Spatial coherence: longitudinal and transverse The correlation of the phase of a light wave between different locations.
20 The coherence time is the reciprocal of the bandwidth (related to monochromaticity). The coherence time is given by: 1/ v c where is the light bandwidth (the width of the spectrum). Sunlight is temporally very incoherent because its bandwidth is very large (the entire visible spectrum). Lasers can have coherence times as long as about a second, which is amazing; that's >10 14 cycles!
21 The Temporal Coherence Time and the Spatial Coherence Length The temporal coherence time is the time the wave-fronts remain equally spaced. That is, the field remains sinusoidal with one wavelength: Temporal Coherence Time, c The transverse spatial coherence length is the distance over which the beam wave-fronts remain flat: Transverse Spatial Coherence Length Since there are two transverse dimensions, we can define a coherence area.
22 Spatial and Temporal Coherence Beams can be coherent or only partially coherent (indeed, even incoherent) in both space and time. Spatial and Temporal Coherence: Temporal Coherence; Spatial Incoherence Spatial Coherence; Temporal Incoherence Spatial and Temporal Incoherence
23 Interference Young Interference Experiment
24 Coherence (chapter 12) Completely incoherent waves: no interference fringes Completely coherent waves: interference fringes best pronounced Laser Add glass plate Laser Lamp Add glass plate Lamp temporal coherence
25 Coherence I = I 1 +I 2 + I 12 T I 12 E t E2 1 t cross-correlation I 12 E1tE2 t T Temporal coherence length is reflected in cross-correlation
26 Visibility Visibility: V I I max max I I min min V 2 I 1 I 1 I I Complex degree of coherence: 12 E 1 * t E t E 2 1 T Coherent limit: 12 = 1 Incoherent limit: 12 = 0 Partial coherence: 0< 12 <1 2 E 2 2 T T
27 Examples 12 = = = 0.062
28 Spatial coherence: extended source For double slit: V sinc ab l
29 The spatial coherence depends on the emitter size and its distance away. The van Cittert-Zernike Theorem states that the spatial coherence area A c is given by: where d is the diameter of the light source and D is the distance away. c 2 2 D 2 d Basically, wave-fronts smooth out as they propagate away from the source. Starlight is spatially very coherent because stars are very far away.
30 The Michelson stellar interferometer 1. Case of double star (equal intensities) interference disappears when: h 0 2 angular distance between the stars 2. Single star, interference disappears when: h angular diameter of the star
31 Betelgeuse -Orion, the first star for which diameter was established in 1920 h h = 121, 0 = 570 nm rad 0.047" From known distance: diameter = 240 million miles (280 times larger than sun)
32 Michelson Interferometer
33
34 Laser Types Lasers can be divided into groups according to different criteria: 1. The state of matter of the active medium: solid, liquid, gas, or plasma. 2. The spectral range of the laser wavelength: visible, Infra-Red (IR), etc. 3. The excitation (pumping) method of the active medium: Optical pumping, electric pumping, etc. 4. The characteristics of the radiation emitted from the laser. 5. The number of energy levels which participate in the lasing process.
35 Classification by active medium Gas lasers (atoms, ions, molecules) Solid-state lasers Semiconductor lasers Diode lasers Unipolar (quantum cascade) lasers Dye lasers (liquid) X-ray lasers Free electron lasers
36 Types of Lasers Solid-state lasers have lasing material distributed in a solid matrix (such as ruby or neodymium:yttrium-aluminum garnet "YAG"). Flash lamps are the most common power source. The Nd:YAG laser emits infrared light at nm. Semiconductor lasers, sometimes called diode lasers, are pn junctions. Current is the pump source. Applications: laser printers or CD/DVD/BlueRay players. Dye lasers use complex organic dyes, such as rhodamine 6G, in liquid solution or suspension as lasing media. They are tunable over a broad range of wavelengths. Gas lasers are pumped by current. Helium-Neon lases in the visible and IR. Argon lases in the visible and UV. CO 2 lasers emit light in the far-infrared (10.6 mm), and are used for cutting hard materials. Excimer lasers (from the terms excited and dimers) use reactive gases, such as chlorine and fluorine, mixed with inert gases such as argon, krypton, or xenon. When electrically stimulated, a pseudo molecule (dimer) is produced. Excimers lase in the UV.
37 The Ruby Laser Invented in 1960 by Ted Maiman at Hughes Research Labs, it was the first laser. Ruby is a three-level system, so you have to hit it hard.
38 Solid state lasers Nd ions in YAG crystal host
39 Semiconductor lasers: Diode laser
40 Semiconductor lasers Conventional semiconductor laser diode laser: CB material VB Quantum cascade laser: unipolar semiconductor laser using intersubband transitions QClaser: CB layer thickness
41 Gas Lasers The laser active medium is a gas at a low pressure (A few milli-torr). The main reasons for using low pressure are: To enable an electric discharge in a long path, while the electrodes are at both ends of a long tube. To obtain narrow spectral width not expanded by collisions between atoms. The first gas laser was operated by T. H. Maiman in 1961, one year after the first laser (Ruby) was demonstrated. The first gas laser was a Helium-Neon laser, operating at a wavelength of [nm] (Near Infra-Red).
42 Pumping by electric discharge
43 The Helium- Neon Laser Energetic electrons in a glow discharge collide with and excite He atoms, which then collide with and transfer the excitation to Ne atoms, an ideal 4-level system.
44
45 Argon ion laser High power, but low efficiency
46 Carbon Dioxide Laser The CO 2 laser operates analogously. N 2 is pumped, transferring the energy to CO 2.
47 CO 2 Laser
48
49 Gas lasers exist in nature! Stellar atmospheres Planetary atmospheres Interstellar medium
50 CO 2 laser in the Martian atmosphere The atmosphere is thin and the sun is dim, but the gain per molecule is high, and the pathlength is long. Detuning from line center (MHz)
51 Free electron lasers
52
53 Applications Industrial applications Medical (surgery, diagnostics) Military (weapons, blinders, target pointers, ) Daily (optical communications, optical storage, memory) Research
54 Inertial confinement for nuclear fusion
55 Laser Fusion
56 D + T ==> 4 He + n [MeV]
Instructor: Welcome to. Phys 774: Principles of Spectroscopy. Fall How can we produce EM waves? Spectrum of Electromagnetic Radiation and Light
Welcome to Phys 774: Principles of Spectroscopy Fall 2007 Instructor: Andrei Sirenko Associate Professor at the Dept. of Physics, NJIT http://web.njit.edu/~sirenko 476 Tiernan Office hours: After the classes
More informationEngineering Medical Optics BME136/251 Winter 2017
Engineering Medical Optics BME136/251 Winter 2017 Monday/Wednesday 2:00-3:20 p.m. Beckman Laser Institute Library, MSTB 214 (lab) Teaching Assistants (Office hours: Every Tuesday at 2pm outside of the
More informationUnit-2 LASER. Syllabus: Properties of lasers, types of lasers, derivation of Einstein A & B Coefficients, Working He-Ne and Ruby lasers.
Unit-2 LASER Syllabus: Properties of lasers, types of lasers, derivation of Einstein A & B Coefficients, Working He-Ne and Ruby lasers. Page 1 LASER: The word LASER is acronym for light amplification by
More informationMaterialwissenschaft und Nanotechnologie. Introduction to Lasers
Materialwissenschaft und Nanotechnologie Introduction to Lasers Dr. Andrés Lasagni Lehrstuhl für Funktionswerkstoffe Sommersemester 007 1-Introduction to LASER Contents: Light sources LASER definition
More informationLasers and Electro-optics
Lasers and Electro-optics Second Edition CHRISTOPHER C. DAVIS University of Maryland III ^0 CAMBRIDGE UNIVERSITY PRESS Preface to the Second Edition page xv 1 Electromagnetic waves, light, and lasers 1
More informationLasers & Holography. Ulrich Heintz Brown University. 4/5/2016 Ulrich Heintz - PHYS 1560 Lecture 10 1
Lasers & Holography Ulrich Heintz Brown University 4/5/2016 Ulrich Heintz - PHYS 1560 Lecture 10 1 Lecture schedule Date Topic Thu, Jan 28 Introductory meeting Tue, Feb 2 Safety training Thu, Feb 4 Lab
More informationUnit I LASER Engineering Physics
Introduction LASER stands for light Amplification by Stimulated Emission of Radiation. The theoretical basis for the development of laser was provided by Albert Einstein in 1917. In 1960, the first laser
More informationChemistry Instrumental Analysis Lecture 5. Chem 4631
Chemistry 4631 Instrumental Analysis Lecture 5 Light Amplification by Stimulated Emission of Radiation High Intensities Narrow Bandwidths Coherent Outputs Applications CD/DVD Readers Fiber Optics Spectroscopy
More informationLaser Physics OXFORD UNIVERSITY PRESS SIMON HOOKER COLIN WEBB. and. Department of Physics, University of Oxford
Laser Physics SIMON HOOKER and COLIN WEBB Department of Physics, University of Oxford OXFORD UNIVERSITY PRESS Contents 1 Introduction 1.1 The laser 1.2 Electromagnetic radiation in a closed cavity 1.2.1
More informationWhat do we study and do?
What do we study and do? Light comes from electrons transitioning from higher energy to lower energy levels. Wave-particle nature of light Wave nature: refraction, diffraction, interference (labs) Particle
More information23. Lasers II. Four-level systems are the best for lasers. Steady-state conditions: - threshold. - longitudinal modes. Some laser examples
23. Lasers II Four-level systems are the best for lasers Steady-state conditions: - threshold - longitudinal modes Some laser examples The teleforce ray will send concentrated beams of particles through
More informationLaser Types Two main types depending on time operation Continuous Wave (CW) Pulsed operation Pulsed is easier, CW more useful
Main Requirements of the Laser Optical Resonator Cavity Laser Gain Medium of 2, 3 or 4 level types in the Cavity Sufficient means of Excitation (called pumping) eg. light, current, chemical reaction Population
More informationLaserphysik. Prof. Yong Lei & Dr. Yang Xu. Fachgebiet Angewandte Nanophysik, Institut für Physik
Laserphysik Prof. Yong Lei & Dr. Yang Xu Fachgebiet Angewandte Nanophysik, Institut für Physik Contact: yong.lei@tu-ilmenau.de; yang.xu@tu-ilmenau.de Office: Heisenbergbau V 202, Unterpörlitzer Straße
More informationOPAC 101 Introduction to Optics
OPAC 101 Introduction to Optics Topic 2 Light Sources Department of http://www1.gantep.edu.tr/~bingul/opac101 Optical & Acustical Engineering Gaziantep University Sep 2017 Sayfa 1 Light Sources: maybe
More informationF. Elohim Becerra Chavez
F. Elohim Becerra Chavez Email:fbecerra@unm.edu Office: P&A 19 Phone: 505 277-2673 Lectures: Monday and Wednesday, 5:30-6:45 pm P&A Room 184. Textbook: Many good ones (see webpage) Lectures follow order
More informationL.A.S.E.R. LIGHT AMPLIFICATION. EMISSION of RADIATION
Lasers L.A.S.E.R. LIGHT AMPLIFICATION by STIMULATED EMISSION of RADIATION History of Lasers and Related Discoveries 1917 Stimulated emission proposed by Einstein 1947 Holography (Gabor, Physics Nobel Prize
More informationMansoor Sheik-Bahae. Class meeting times: Mondays, Wednesdays 17:30-18:45 am; Physics and Astronomy, Room 184
Mansoor Sheik-Bahae Office: Physics & Astronomy Rm. 1109 (North Wing) Phone: 277-2080 E-mail: msb@unm.edu To see me in my office, please make an appointment (call or email). Class meeting times: Mondays,
More informationMODERN OPTICS. P47 Optics: Unit 9
MODERN OPTICS P47 Optics: Unit 9 Course Outline Unit 1: Electromagnetic Waves Unit 2: Interaction with Matter Unit 3: Geometric Optics Unit 4: Superposition of Waves Unit 5: Polarization Unit 6: Interference
More informationIn a metal, how does the probability distribution of an electron look like at absolute zero?
1 Lecture 6 Laser 2 In a metal, how does the probability distribution of an electron look like at absolute zero? 3 (Atom) Energy Levels For atoms, I draw a lower horizontal to indicate its lowest energy
More informationEE485 Introduction to Photonics
Pattern formed by fluorescence of quantum dots EE485 Introduction to Photonics Photon and Laser Basics 1. Photon properties 2. Laser basics 3. Characteristics of laser beams Reading: Pedrotti 3, Sec. 1.2,
More informationWhat Makes a Laser Light Amplification by Stimulated Emission of Radiation Main Requirements of the Laser Laser Gain Medium (provides the light
What Makes a Laser Light Amplification by Stimulated Emission of Radiation Main Requirements of the Laser Laser Gain Medium (provides the light amplification) Optical Resonator Cavity (greatly increase
More informationHomework 1. Property LASER Incandescent Bulb
Homework 1 Solution: a) LASER light is spectrally pure, single wavelength, and they are coherent, i.e. all the photons are in phase. As a result, the beam of a laser light tends to stay as beam, and not
More informationLaser Types Two main types depending on time operation Continuous Wave (CW) Pulsed operation Pulsed is easier, CW more useful
What Makes a Laser Light Amplification by Stimulated Emission of Radiation Main Requirements of the Laser Laser Gain Medium (provides the light amplification) Optical Resonator Cavity (greatly increase
More informationLaser Fundamentals and its Applications. Photonic Network By Dr. M H Zaidi
Laser Fundamentals and its Applications LASER LASER is acronym of Light Amplification by Stimulated Emission of Radiation. http://www.semicon.toshiba.co.jp Lasers Outline Introduction and Overview Theory
More informationInterested in exploring science or math teaching as a career?
Interested in exploring science or math teaching as a career? Start with Step 1: EDUC 2020 (1 credit) Real experience teaching real kids! No commitment to continue with education courses Registration priority
More informationOPTICAL GAIN AND LASERS
OPTICAL GAIN AND LASERS 01-02-1 BY DAVID ROCKWELL DIRECTOR, RESEARCH & DEVELOPMENT fsona COMMUNICATIONS MARCH 6, 2001 OUTLINE 01-02-2 I. DEFINITIONS, BASIC CONCEPTS II. III. IV. OPTICAL GAIN AND ABSORPTION
More informationOPTI510R: Photonics. Khanh Kieu College of Optical Sciences, University of Arizona Meinel building R.626
OPTI510R: Photonics Khanh Kieu College of Optical Sciences, University of Arizona kkieu@optics.arizona.edu Meinel building R.626 Announcements HW #5 due today April 11 th class will be at 2PM instead of
More informationLight Emission. Today s Topics. Excitation/De-Excitation 10/26/2008. Excitation Emission Spectra Incandescence
Light Emission Excitation Emission Spectra Incandescence Absorption Spectra Today s Topics Excitation/De-Excitation Electron raised to higher energy level Electron emits photon when it drops back down
More informationF. Elohim Becerra Chavez
F. Elohim Becerra Chavez Email:fbecerra@unm.edu Office: P&A 19 Phone: 505 277-2673 Lectures: Tuesday and Thursday, 9:30-10:45 P&A Room 184. Textbook: Laser Electronics (3rd Edition) by Joseph T. Verdeyen.
More informationENGINEERING PHYSICS UNIT I - LASERS SV COLLEGE OF ENGINEERING, KADAPA
Syllabus:- Characteristics of laser spontaneous and stimulated emission of radiation Einstein s coefficients - population inversion excitation mechanism and optical resonator Nd:YAG laser He-Ne laser semiconductor
More informationPHYSICS. The Probability of Occurrence of Absorption from state 1 to state 2 is proportional to the energy density u(v)..
ABSORPTION of RADIATION : PHYSICS The Probability of Occurrence of Absorption from state 1 to state 2 is proportional to the energy density u(v).. of the radiation > P12 = B12 u(v) hv E2 E1 Where as, the
More informationSome Topics in Optics
Some Topics in Optics The HeNe LASER The index of refraction and dispersion Interference The Michelson Interferometer Diffraction Wavemeter Fabry-Pérot Etalon and Interferometer The Helium Neon LASER A
More informationLasers... the optical cavity
Lasers... the optical cavity history principle, intuitive aspects, characteristics 2 levels systems Ti: Helium Al2O3 - Neon model-locked laser laser VCSEL bragg mirrors cleaved facets 13 ptical and/or
More informationPhys 2310 Fri. Dec. 12, 2014 Today s Topics. Begin Chapter 13: Lasers Reading for Next Time
Phys 2310 Fri. Dec. 12, 2014 Today s Topics Begin Chapter 13: Lasers Reading for Next Time 1 Reading this Week By Fri.: Ch. 13 (13.1, 13.3) Lasers, Holography 2 Homework this Week No Homework this chapter.
More informationPhys 2310 Mon. Dec. 4, 2017 Today s Topics. Begin supplementary material: Lasers Reading for Next Time
Phys 2310 Mon. Dec. 4, 2017 Today s Topics Begin supplementary material: Lasers Reading for Next Time 1 By Wed.: Reading this Week Lasers, Holography 2 Homework this Week No Homework this chapter. Finish
More informationLASERS. Dr D. Arun Kumar Assistant Professor Department of Physical Sciences Bannari Amman Institute of Technology Sathyamangalam
LASERS Dr D. Arun Kumar Assistant Professor Department of Physical Sciences Bannari Amman Institute of Technology Sathyamangalam General Objective To understand the principle, characteristics and types
More informationStimulated Emission Devices: LASERS
Stimulated Emission Devices: LASERS 1. Stimulated Emission and Photon Amplification E 2 E 2 E 2 hυ hυ hυ In hυ Out hυ E 1 E 1 E 1 (a) Absorption (b) Spontaneous emission (c) Stimulated emission The Principle
More informationChapter-4 Stimulated emission devices LASERS
Semiconductor Laser Diodes Chapter-4 Stimulated emission devices LASERS The Road Ahead Lasers Basic Principles Applications Gas Lasers Semiconductor Lasers Semiconductor Lasers in Optical Networks Improvement
More informationIntroduction to Laser Material Processing. ME 677: Laser Material Processing Instructor: Ramesh Singh 1
Introduction to Laser Material Processing 1 Outline Brief History Design of Laser cavity Stability Types of Lasers 2 Laser History 1917 - Albert Einstein: Theoretical prediction of stimulated emission
More informationDept. of Physics, MIT Manipal 1
Chapter 1: Optics 1. In the phenomenon of interference, there is A Annihilation of light energy B Addition of energy C Redistribution energy D Creation of energy 2. Interference fringes are obtained using
More informationPRINCIPLES OF PHYSICAL OPTICS
PRINCIPLES OF PHYSICAL OPTICS C. A. Bennett University of North Carolina At Asheville WILEY- INTERSCIENCE A JOHN WILEY & SONS, INC., PUBLICATION CONTENTS Preface 1 The Physics of Waves 1 1.1 Introduction
More informationLasers E 6 E 4 E 3 E 2 E 1
Lasers Laser is an acronym for light amplification by stimulated emission of radiation. Here the process of stimulated emission is used to amplify light radiation. Spontaneous emission: When energy is
More information(b) Spontaneous emission. Absorption, spontaneous (random photon) emission and stimulated emission.
Lecture 10 Stimulated Emission Devices Lasers Stimulated emission and light amplification Einstein coefficients Optical fiber amplifiers Gas laser and He-Ne Laser The output spectrum of a gas laser Laser
More informationSpontaneous and Stimulated Transitions
Laser Physics I PH481/581-VT (Mirov) Spontaneous and Stimulated Transitions Lectures 1-2 Fall 2015 C. Davis, Lasers and Electro-optics 1 A laser is an oscillator of optical frequencies that concentrates
More informationLASERS. Amplifiers: Broad-band communications (avoid down-conversion)
L- LASERS Representative applications: Amplifiers: Broad-band communications (avoid down-conversion) Oscillators: Blasting: Energy States: Hydrogen atom Frequency/distance reference, local oscillators,
More informationIntroduction Fundamentals of laser Types of lasers Semiconductor lasers
Introduction Fundamentals of laser Types of lasers Semiconductor lasers Is it Light Amplification and Stimulated Emission Radiation? No. So what if I know an acronym? What exactly is Light Amplification
More informationOptics, Light and Lasers
Dieter Meschede Optics, Light and Lasers The Practical Approach to Modern Aspects of Photonics and Laser Physics Second, Revised and Enlarged Edition BICENTENNIAL.... n 4 '':- t' 1 8 0 7 $W1LEY 2007 tri
More information2. Discrete means unique, that other states don t overlap it. 3. Electrons in the outer electron shells have greater potential energy.
30 Light Emission Answers and Solutions for Chapter 30 Reading Check Questions 1. At these high frequencies, ultraviolet light is emitted. 2. Discrete means unique, that other states don t overlap it.
More informationδf / δx = σ F (N 2 -N 1 ) ΔF~N 2 -N 1
LASER Light Amplification by Stimulated Emission of Radiation BASIC PROPERTIES O LASER RADIATION Spontaneous emission Incoherence in time Incoherence in space Polychromatic light Small energy density Non-polarized
More informationICPY471. November 20, 2017 Udom Robkob, Physics-MUSC
ICPY471 19 Laser Physics and Systems November 20, 2017 Udom Robkob, Physics-MUSC Topics Laser light Stimulated emission Population inversion Laser gain Laser threshold Laser systems Laser Light LASER=
More informationWhat can laser light do for (or to) me?
What can laser light do for (or to) me? Phys 1020, Day 15: Questions? Refection, refraction LASERS: 14.3 Next Up: Finish lasers Cameras and optics 1 Eyes to web: Final Project Info Light travels more slowly
More informationStimulated Emission. Electrons can absorb photons from medium. Accelerated electrons emit light to return their ground state
Lecture 15 Stimulated Emission Devices- Lasers Stimulated emission and light amplification Einstein coefficients Optical fiber amplifiers Gas laser and He-Ne Laser The output spectrum of a gas laser Laser
More informationChapter9. Amplification of light. Lasers Part 2
Chapter9. Amplification of light. Lasers Part 06... Changhee Lee School of Electrical and Computer Engineering Seoul National Univ. chlee7@snu.ac.kr /9 9. Stimulated emission and thermal radiation The
More informationFigure 1 Relaxation processes within an excited state or the ground state.
Excited State Processes and Application to Lasers The technology of the laser (Light Amplified by Stimulated Emission of Radiation) was developed in the early 1960s. The technology is based on an understanding
More informationLaser Basics. What happens when light (or photon) interact with a matter? Assume photon energy is compatible with energy transition levels.
What happens when light (or photon) interact with a matter? Assume photon energy is compatible with energy transition levels. Electron energy levels in an hydrogen atom n=5 n=4 - + n=3 n=2 13.6 = [ev]
More informationLASERS AGAIN? Phys 1020, Day 17: Questions? LASERS: Next Up: Cameras and optics Eyes to web: Final Project Info
LASERS AGAIN? Phys 1020, Day 17: Questions? LASERS: 14.3 Next Up: Cameras and optics Eyes to web: Final Project Info 1 Group Exercise Your pennies will simulate a two state atom; tails = ground state,
More information-I (PH 6151) UNIT-V PHOTONICS AND FIBRE OPTICS
Engineering Physics -I (PH 6151) UNIT-V PHOTONICS AND FIBRE OPTICS Syllabus: Lasers Spontaneous and stimulated emission Population Inversion -Einstein s co-efficient (Derivation)- types of lasers-nd-yag,co
More informationIntroduction to Laser Material Processing. ME 677: Laser Material Processing Instructor: Ramesh Singh 1
Introduction to Laser Material Processing 1 Outline Brief History Design of Laser cavity Stability Types of Lasers 2 Laser History 1917 - Albert Einstein: Theoretical prediction of stimulated emission
More informationLasers. Optical Fibres
Lasers & Optical Fibres P a g e 2 Contents LASER 1) Coherence 3 2) Interaction of radiation with matter 4 3) Laser fundamentals 5 4) Laser system 5 5) Ruby Laser 6 6) He-Ne Gas Laser 7 7) Semiconductor
More information4 Classical Coherence Theory
This chapter is based largely on Wolf, Introduction to the theory of coherence and polarization of light [? ]. Until now, we have not been concerned with the nature of the light field itself. Instead,
More informationModel Answer (Paper code: AR-7112) M. Sc. (Physics) IV Semester Paper I: Laser Physics and Spectroscopy
Model Answer (Paper code: AR-7112) M. Sc. (Physics) IV Semester Paper I: Laser Physics and Spectroscopy Section I Q1. Answer (i) (b) (ii) (d) (iii) (c) (iv) (c) (v) (a) (vi) (b) (vii) (b) (viii) (a) (ix)
More informationLASER. Challenging MCQ questions by The Physics Cafe. Compiled and selected by The Physics Cafe
LSER hallenging MQ questions by The Physics afe ompiled and selected by The Physics afe www.thephysicsafe.com www.pmc.sg 1 laser point creates a spot on a screen as it reflects 70% of the light striking
More informationRichard Miles and Arthur Dogariu. Mechanical and Aerospace Engineering Princeton University, Princeton, NJ 08540, USA
Richard Miles and Arthur Dogariu Mechanical and Aerospace Engineering Princeton University, Princeton, NJ 08540, USA Workshop on Oxygen Plasma Kinetics Sept 20, 2016 Financial support: ONR and MetroLaser
More informationQUESTION BANK IN PHYSICS
QUESTION BANK IN PHYSICS LASERS. Name some properties, which make laser light different from ordinary light. () {JUN 5. The output power of a given laser is mw and the emitted wavelength is 630nm. Calculate
More informationTHETOPPERSWAY.COM. Laser System. Principle of Lasers. Spontaneous Emission and Stimulated Emission. Page 1
LASER is the abbreviation of Light Amplification by the Stimulated Emission of Radiation. It is a device that creates a narrow and low-divergent beam of coherent light, while most other light sources emit
More informationChapter 5. Semiconductor Laser
Chapter 5 Semiconductor Laser 5.0 Introduction Laser is an acronym for light amplification by stimulated emission of radiation. Albert Einstein in 1917 showed that the process of stimulated emission must
More informationBANNARI AMMAN INSTITUTE OF TECHNOLOGY SATHYAMANGALAM DEPARTMENT OF PHYSICAL SCIENCES. UNIT II Applied Optics
BANNAI AMMAN INSTITTE OF TECHNOLOGY SATHYAMANGALAM DEPATMENT OF PHYSICAL SCIENCES NIT II Applied Optics PAT A A1 The superimposition of one light wave over another is called as a) interference b) Diffraction
More informationMetal Vapour Lasers Use vapoured metal as a gain medium Developed by W. Silfvast (1966) Two types: Ionized Metal vapour (He-Cd) Neutral Metal vapour
Metal Vapour Lasers Use vapoured metal as a gain medium Developed by W. Silfvast (1966) Two types: Ionized Metal vapour (He-Cd) Neutral Metal vapour (Cu) All operate by vaporizing metal in container Helium
More informationWhat are Lasers? Light Amplification by Stimulated Emission of Radiation LASER Light emitted at very narrow wavelength bands (monochromatic) Light
What are Lasers? What are Lasers? Light Amplification by Stimulated Emission of Radiation LASER Light emitted at very narrow wavelength bands (monochromatic) Light emitted in a directed beam Light is coherenent
More informationX-Rays From Laser Plasmas
X-Rays From Laser Plasmas Generation and Applications I. C. E. TURCU CLRC Rutherford Appleton Laboratory, UK and J. B. DANCE JOHN WILEY & SONS Chichester New York Weinheim Brisbane Singapore Toronto Contents
More informationLASER. Light Amplification by Stimulated Emission of Radiation
LASER Light Amplification by Stimulated Emission of Radiation Laser Fundamentals The light emitted from a laser is monochromatic, that is, it is of one color/wavelength. In contrast, ordinary white light
More informationElectricity & Optics
Physics 24100 Electricity & Optics Lecture 26 Chapter 33 sec. 1-4 Fall 2017 Semester Professor Koltick Interference of Light Interference phenomena are a consequence of the wave-like nature of light Electric
More informationOptics, Optoelectronics and Photonics
Optics, Optoelectronics and Photonics Engineering Principles and Applications Alan Billings Emeritus Professor, University of Western Australia New York London Toronto Sydney Tokyo Singapore v Contents
More informationSteady state operation : g = 1
Laser = active medium + cavity L active medium R1 R2 47 47 Net gain per round trip L active medium R1 R2 losses gain (intrinsic) g Intensity after one round trip = = R1$ R2$ exp6 2^b-ah $ l@ I0 Steady
More informationSpecific Laser Systems
18/01/2017 Specific Laser Systems Electro-Optics & Applications Prof. Elias N. Glytsis School of Electrical & Computer Engineering National Technical University of Athens Quantum Efficiency of Laser 3-Level
More informationChapter 13. Phys 322 Lecture 34. Modern optics
Chapter 13 Phys 3 Lecture 34 Modern optics Blackbodies and Lasers* Blackbodies Stimulated Emission Gain and Inversion The Laser Four-level System Threshold Some lasers Pump Fast decay Laser Fast decay
More informationSemiconductor Lasers EECE 484. Winter Dr. Lukas Chrostowski
Semiconductor Lasers EECE 484 Winter 2013 Dr. Lukas Chrostowski 1 484 - Course Information Web Page: http://siepic.ubc.ca/eece484 (password DBR, check for updates) + Piazza, https://piazza.com/ubc.ca/winterterm22013/eece484
More informationExcimer Lasers Currently best UV laser sources Consist two atom types which repel each other eg nobel gas and halide or oxide which normally do not
Excimer Lasers Currently best UV laser sources Consist two atom types which repel each other eg nobel gas and halide or oxide which normally do not bond But when excited/ionized these atoms attract Bound
More informationLASER. Light Amplification by Stimulated Emission of Radiation. Principle and applications
LASER Light Amplification by Stimulated Emission of Radiation Principle and applications Stimulated Emission process which makes lasers possible, was proposed in 1917 by Albert Einstein. No one realized
More informationFar IR Gas Lasers microns wavelengths, THz frequency Called Terahertz lasers or FIR lasers At this wavelength behaves more like
Far IR Gas Lasers 10-1500 microns wavelengths, 300 10 THz frequency Called Terahertz lasers or FIR lasers At this wavelength behaves more like microwave signal than light Created by Molecular vibronic
More informationExperiment 3 1. The Michelson Interferometer and the He- Ne Laser Physics 2150 Experiment No. 3 University of Colorado
Experiment 3 1 Introduction The Michelson Interferometer and the He- Ne Laser Physics 2150 Experiment No. 3 University of Colorado The Michelson interferometer is one example of an optical interferometer.
More informationPhysical Optics. Lecture 8: Laser Michael Kempe.
Physical Optics Lecture 8: Laser 2018-12-13 Michael Kempe www.iap.uni-jena.de Physical Optics: Content 2 No Date Subject Ref Detailed Content 1 18.10. Wave optics G Complex fields, wave equation, k-vectors,
More informationAr and Kr ion lasers
Types of Lasers Ar and Kr ion lasers Nd:YAG and Nd:YLF lasers CO 2 lasers Excimer lasers Dye lasers Transition metal lasers Optical parametric amplification Ar and Kr ion lasers Noble gas ions are created
More information1) Introduction 2) Photo electric effect 3) Dual nature of matter 4) Bohr s atom model 5) LASERS
1) Introduction 2) Photo electric effect 3) Dual nature of matter 4) Bohr s atom model 5) LASERS 1. Introduction Types of electron emission, Dunnington s method, different types of spectra, Fraunhoffer
More information10.8 LASERS Principle of Laser Induced Absorption
10.8 LASERS The word Laser stands for Light Amplification by Stimulated Emission of Radiations. Laser is biggest achieve of twentieth century in the field of research. The first laser was developed by
More informationB.Tech. First Semester Examination Physics-1 (PHY-101F)
B.Tech. First Semester Examination Physics-1 (PHY-101F) Note : Attempt FIVE questions in all taking least two questions from each Part. All questions carry equal marks Part-A Q. 1. (a) What are Newton's
More informationSignal regeneration - optical amplifiers
Signal regeneration - optical amplifiers In any atom or solid, the state of the electrons can change by: 1) Stimulated absorption - in the presence of a light wave, a photon is absorbed, the electron is
More information22. Lasers. Stimulated Emission: Gain. Population Inversion. Rate equation analysis. Two-level, three-level, and four-level systems
. Lasers Stimulated Emission: Gain Population Inversion Rate equation analysis Two-level, three-level, and four-level systems What is a laser? LASER: Light Amplification by Stimulated Emission of Radiation
More informationChapter 28 Assignment Solutions
Chapter 28 Assignment Solutions Page 770 #23-26, 29-30, 43-48, 55 23) Complete the following concept map using these terms: energy levels, fixed electron radii, Bohr model, photon emission and absorption,
More informationInterference, Diffraction and Fourier Theory. ATI 2014 Lecture 02! Keller and Kenworthy
Interference, Diffraction and Fourier Theory ATI 2014 Lecture 02! Keller and Kenworthy The three major branches of optics Geometrical Optics Light travels as straight rays Physical Optics Light can be
More informationThe Photon Concept. Modern Physics [2] How are x-rays produced? Gamma rays. X-ray and gamma ray photons. X-rays & gamma rays How lasers work
Modern Physics [2] X-rays & gamma rays How lasers work Medical applications of lasers Applications of high power lasers Medical imaging techniques CAT scans MRI s The Photon Concept a beam of light waves
More informationWhat are Lasers? Light Amplification by Stimulated Emission of Radiation LASER Light emitted at very narrow wavelength bands (monochromatic) Light
What are Lasers? What are Lasers? Light Amplification by Stimulated Emission of Radiation LASER Light emitted at very narrow wavelength bands (monochromatic) Light emitted in a directed beam Light is coherenent
More informationPrinciples of Lasers. Cheng Wang. Phone: Office: SEM 318
Principles of Lasers Cheng Wang Phone: 20685263 Office: SEM 318 wangcheng1@shanghaitech.edu.cn The course 2 4 credits, 64 credit hours, 16 weeks, 32 lectures 70% exame, 30% project including lab Reference:
More informationChapter 7: Optical Properties of Solids. Interaction of light with atoms. Insert Fig Allowed and forbidden electronic transitions
Chapter 7: Optical Properties of Solids Interaction of light with atoms Insert Fig. 8.1 Allowed and forbidden electronic transitions 1 Insert Fig. 8.3 or equivalent Ti 3+ absorption: e g t 2g 2 Ruby Laser
More informationInnovation and Development of Study Field. nano.tul.cz
Innovation and Development of Study Field Nanomaterials at the Technical University of Liberec nano.tul.cz These materials have been developed within the ESF project: Innovation and development of study
More informationChapter 2 Laser Light Amplification by Stimulated Emission of Radiation
Chapter Laser Light Ampliication by Stimulated Emission o Radiation Part I How does an object emit light or radiation? Blackbody Radiation Solids heated to very high temperatures emit visible light (glow)
More informationP.M. THURSDAY, 21 May hours. Write your name, centre number and candidate number in the spaces at the top of this page.
Candidate Name Centre Number Candidate Number GCE AS/A level 1322/01 New AS PHYSICS ASSESSMENT UNIT PH2: WAVES AND PARTICLES P.M. THURSDAY, 21 May 2009 1 1 4 hours ADDITIONAL MATERIALS In addition to this
More informationFree Electron Laser. Project report: Synchrotron radiation. Sadaf Jamil Rana
Free Electron Laser Project report: Synchrotron radiation By Sadaf Jamil Rana History of Free-Electron Laser (FEL) The FEL is the result of many years of theoretical and experimental work on the generation
More informationJRE Group of Institutions ASSIGNMENT # 1 Special Theory of Relativity
ASSIGNMENT # 1 Special Theory of Relativity 1. What was the objective of conducting the Michelson-Morley experiment? Describe the experiment. How is the negative result of the experiment interpreted? 2.
More informationLecture # 09: Technical Basis for Optical Instrumentation
AerE 344 Lecture Notes Lecture # 09: Technical Basis for Optical Instrumentation Dr. Hui Hu Department of Aerospace Engineering Iowa State University Ames, Iowa 50011, U.S.A The nature of light According
More information