Classical theory of free electron lasers a text for students and researchers eric b szarmes chapter 1 introduction and overview 1. Introduction to free electron lasers andy wolski the cockcroft institute, and the university of liverpool, uk cas. Workie department of physics university of cincinnati cincinnati, ohio 45221 november 26, 01 abstract a tunable coherent and high peak power sources have been very usefull in many applications. Free electron lasers free electron lasers fels are sources of synchrotron radiation that can produce radiation with peak power and brightness orders of magnitude larger than the radiation produced by conventional sources such as dipoles and wigglers. According to the classical free electron theory the value of specific heat. Various damage mechanisms in carbon and silicon materials under femtosecond xray irradiation. Pdf an introduction to the theory of free electron lasers. Atomic selectrons are delocalised due to overlap of outer orbits. The inverse free electron laser experiment at the neptune laboratory at ucla accelerated electrons from 14.
Read the latest articles of nuclear instruments and methods in physics research section a. Theory of a free electron laser with a gaussian optical undulator article pdf available in ieee journal of quantum electronics 248. Tutorial on classical free electron laser theory sciencedirect. Pdf highgain freeelectron lasers fels are being developed as. The valence electrons of atoms are free to move about the whole volume of the metals like the molecules of a perfect gas in a container. Classical theory of a freeelectron laser sciencedirect. Scully department of physics and optical sciences center, university of arizona, tucson, arizona 85721, usa and w. Physics of the free electron laser the free electron laser can produce intense, coherent light as the result of the interaction between an electron beam and an electric field of light. This textbook focuses on the fully classical theory of fels with application to fel oscillators and develops the fundamentals of fel theory in sufficient depth to provide both a solid understanding of fel physics and a solid background for research in the field. Contrasting with semiclassical theory, which depicts electromagnetic radiation as a classical wave, qed representations of quantized light fully embrace the concept of the photon.
Introduction to free electron lasers the nature of light gaussian beam laser beam emittance. His current research interests include the theory and design of novel optical resonators for highresolution free electron laser spectroscopy, xray generation and highfield physics. In an atom electrons revolue around the nucleus and a metal is composed of such atoms. Molecular dynamics md methods with classical potentials or. This model is also considered in the calculations of classical electron radius4.
Quantum theory of free electron sommerfield theory duration. In this paper the authors describe the extension of one such code tda, which in its original form could only be used to study free electron laser. Theory group, theory department, max planck institute for the structure and dynamics of matter, max planck society. In this paper the physical process of new type of coherent. Extension of the freeelectron laser amplifier code tda to. According to classical free electron theory of metals electrical conductivity is given by, from the above equation, relation between temperature and electrical conductivity is given by hence, classical free electron fails to explain the temperature dependence of electrical conductivity.
Classical theory of freeelectron lasers book iopscience. In this thesis we developed a three dimensional 3d quantum theory for a fel with a laser wiggler, based on a discrete wigner function formalism taking into account the longitudinal momentum quantization. Extensions of the lorentzmaxwell theory are straight forward and can be solved analytically, or on a small computer. Volume free electron laser with a photonic crystal crystallike arti. This lack of suppression by the inverse mass of the loop particle contradicts the appelquistcarazzone decoupling theorem 24. The classical formalism for an electromagnetic field has been used to formulate a theory for the free electron laser because the electron beam used for the free electron laser was not very well refined in the past, its formulation by using quantum mechanical formalism was not required. Then, the electron and field dynamics are deeply investigated from a classical point of view, the validity of the classical approximation also being commented on. Engineering physics vtu notes pdf ep vtu pdf smartzworld. Undulator fel dynamics lectures on the free electron.
The free electron laser fel will be an outstanding tool for research and industrial application. After a qualitative discussion, aimed at framing the present and the projected potential of the undulator fel within the general context of the laser sources, the operating fel regimes are illustrated in some detail. Pdf this report is a primer introduction on the sources of coherent. Introduction to our knowledge there are only two kinds of theories of free electron lasers fel. Electron is an open source library developed by github for building crossplatform desktop applications with html, css, and javascript. We will therefore return to the quantum aspects of ufel in the concluding part of the paper. However due to the recent refinements of the electron. Recent advances in tabletop, ultrahigh intensity lasers have led to significant renewed interest in the classic problem of thomson scattering. Stimulated processes are the basic phenomena in laser devices, operating either as amplifiers or as optical oscillators. This means that numerical calculations are performed using a classical ensemble method that treats the entire system, both the laser. Free electron lasers as a classical electron device with longtime interaction. The free electron laser is tunable and has the widest frequency range of any laser type, currently ranging in wavelength from microwaves, through terahertz radiation and infrared, to the visible spectrum, ultraviolet. Xfel 2015 xfel 2015 swissfel 2017 lcls ii 2017 fermi 2010 flash 2005.
Classical relativistic electrodynamics theory of light. Fundamental physics at free electron lasers pair creation in overlap of electron beam crossed with laser beam illustration from marklund,lundin 08 two stage process. Use features like bookmarks, note taking and highlighting while reading classical theory of freeelectron lasers. The theory was originally proposed in 1900 to describe and correlate the electrical and thermal properties of metals. Pdf tutorial lecture on field electron emission theory.
An important current application of these scattering processes is the generation of ultrashortpulseduration x rays. Drude treated the free electrons as a classical ideal gas but the electrons should collide with the stationary ions, not with each other. Various damage mechanisms in carbon and silicon materials. It is found that the orbit, and therefore its nonlinear scattering spectra, depends on the amplitude and on the phase at which the electron sees the laser electric field. The aim is to keep the physical and mathematical arguments at a level within the grasp of an. Although the laser operation is best described in the framework of a semiclassical theory, in which the electromagnetic field is not treated quantum mechanically, the basic processes are better understood if we quantize the field. An analysis of the linearized system allows the definition and. The quantum freeelectron laser university of strathclyde. Theoretical analysis of operation of volume free electron laser using a grid photonic crystal with variable period is accompanied by the discussion of.
Pelligrini, introduction to the physics of the free electron laser, laser handbook, vol. Freeelectron theory of metals article about freeelectron. Center for free electron laser science, 22761 hamburg, germany dated. In this tutorial, the classical theory of nonlinear thomson scattering of an electron in an intense laser. In 1998 he joined the faculty of the university of hawaii where he is currently an associate professor of physics. This idea was given by drude and he utilized it to explain many properties of metals satisfactorily such as electrical conductivity, thermal conductivity etc. On the other hand, since quantum mechanics is the more fundamental theory. The basic principle of the free electron laser can be described within the. Theory and practice of free electron lasers particle accelerator school day 1 dinh nguyen, steven russell. Semiclassical theory of a free electron laser sciencedirect. The realization of a free electron laser fel operating in the quantum regime could provide a compact and monochromatic xray source. The laser nearest and dearest to most accelerator physicists hearts the free electron laser fel, turns out not to be a laser at all according to our definition, but a purely classical device.
The phenomena such a photoelectric effect, compton effect and the black body radiation couldnt be explained by classical free electron theory. The theory is formulated under completely classical hypotheses. The light is emitted as the electron beam bunches into many very thin. Volume free electron laser with a grid photonic crystal. Fundamentals of free electron lasers, a group of tutorial papers. In the following we sketch the fully classical theory following atomicmolecular laser theory based on the coupled maxwellbloch theory as it was first published in 1976. On the classical singleparticle theory of free electron laser. In this model, electron is considered as a spherical shell with radius a carrying charge e and having mass m. Volume 39, number 5 optics communications 1 november 1981 the quantum and classical aspects of the free electron laser theory g. Physics of the freeelectron laser lasers, photonics, and. Pdf analytical theory of shortpulse freeelectron laser. Lectures on the free electron laser theory and related topics g.
The treatment of a metal as containing a gas of electrons completely free to move within it. Colson, tutorial on classical free electron laser theory, nuclear instruments and methods in physics research a237, 19 1985. Nov 23, 2015 a free electron laser, is a type of laser that uses veryhighspeed electrons that move freely through a magnetic structure, hence the term free electron as the lasing medium. The free electrons traverse a series of alternating magnets, called a wiggler, and radiate light at wavelengths depending on electrons energy, wiggler period and magnetic field. A simple model for the nonlinear evolution of a shortpulse free electron laser oscillator in the small gain regime is derived.
The semi classical theory agrees with the classical theory of a free electron laser and gives more knowledge. Extensions of the lorentzmaxwell theory are straight forward and can be solved analytically. Colson w b 1990 classical free electron laser theory laser handbook vol 6. In fact fel is based on the stimulated emission of virtual photons by a. Hence, the fel is broadely viewed as the prime example of a classical laser 1. Free electron lasers produced by the resonant interaction of a relativistic electron beam with a photon beam in an undulator tunable, powerful, coherent radiation sources 1977 first operation of a free electron laser at stanford university today 22 free electron lasers operating worldwide 19 fels proposed or in construction. A free electron laser fel is a kind of laser whose lasing medium consists of veryhighspeed electrons moving freely through a magnetic structure, hence the term free electron. Pdf theory of a freeelectron laser with a gaussian. A short history of electron sources for and the operating characteristics of the free. A text for students and researchers iop concise physics.
To maintain the resonant condition with the accelerating. Pdf introduction to the physics of free electron laser and. The quantum and classical aspects of the free electron. Simple models for classical electron radius and spin. Introduction to free electron lasers and fourthgeneration. The freeelectron laser singleparticle multimode classical. Volume 18, number 4 optics communications september 1976 classical theory of a freeelectron laser f. Fundamentals, types, and operations n n e 0 e e 1 e 3 e 0 e e 1 2 fast decay fast decay fast decay pumping pumping lasing lasing a b figure 1. Electron accomplishes this by combining chromium and node.
Introduction the classical formalism for an electromagnetic field was used to advance a theory for the free electron laser. What are the merits of classical free electron theory. Renieri comitato nazionale energia nucleare, centro di rascati, c. Theory tutorial on classical free electron laser theory w. The free electron laser is tunable and has the widest frequency range of any laser type, 3 currently ranging in wavelength from microwaves, through terahertz. One of the key frameworks for developing the theory of lightmatter interactions in modern optics and photonics is quantum electrodynamics qed. Each electron emits a wave train with n u cycles 1n u n u. January 3, 2018 abstract the e ect of electron phonon coupling in materials can be interpreted as a dressing of the electronic structure by the lattice vibration, leading to vibrational replicas and hybridization of electronic states. This is unlike conventional microwave vacuum tubes.
Example of the development of microbunching of the xfel electron beam along. Free electron laser fel theory is extended to explain several effects. N 1 to achieve the condition of population inversion between e 2 and e 1 at moderate pumping. The gyrotron is a type of free electron maser which generates highfrequency electromagnetic radiation by stimulated cyclotron resonance of electrons moving through a strong magnetic field.
It is found that the orbit, and therefore its nonlinear scattering spectra, depends on the amplitude and on the phase at which the electron sees the laser electric. Metals drudes classical theory theory by paul drude in 1900, only three years after the electron was discovered. Volume 18, number 4 optics communications september 1976 classical theory of a free electron laser f. Oct 12, 2007 in this paper the essentia features of the free electron laser operation are investigated in the multimode regime and in the framework of a singleparticle theory. Jun 15, 2018 neglecting the electron electron interaction and the electron ion interaction, it appears as if the electrons move in a confined box with periodic collision with ions in the lattice. A text for students and researchers iop concise physics kindle edition by szarmes, eric b download it once and read it on your kindle device, pc, phones or tablets. Nuclear instruments and methods in physics research a231 1985 19 northholland, amsterdam section i. This book describes the physical fundamentals on the basis of classical mechanics, electrodynamics, and the kinetic theory of charged particle beams, and will be suitable for graduate students and scientists alike. Radiation from an oscillating electric charge consider a single oscillating electron. The classical free electron theory ofmetals drude lorentz theory of metals lecture2postulates. Pdf highgain freeelectron laser theory, introduction. A theoretical study of the possibility of a free electron laser in the xuv and soft xray region of the spectrum, using a counterpropagaing co 2 laser beam as an undulator, is presented.
Basic physical processes and principles of free electron. Waves in relativistic electron beams presents an advanced course of classical electrodynamics with application to the generation of highpower coherent radiation in the microwave to opticalwave regions. Lectures on the free electron laser theory and related topics. The investigation of many interesting, complex phenomena in a free electron laser fel requires the use of numerical computer codes. The question of a classical theory of fel operation was very much in the air in the early days 19731976. A brief discussion looks at highgain collective effects, short pulse effects, harmonics, energy spread and emittance, transverse diffraction, and noise.
Center for free electron laser science, 22761 hamburg. However, because the electron beam employed in the free electron laser was not refined very well in the past, its formulation by quantum mechanical formalism was not considered seriously. Here you can download the engineering physics vtu notes pdf ep vtu pdf of as per vtu syllabus. Unit1 classical free electron theory physics duration. No stimulated emission, but a similar instability with coherent coupling between the field and the emitters, and exponential growth. Quantum electrodynamics in modern optics and photonics. Tutorial on classical free electron laser theory nasaads.