Introduction to laser technology for an electron to jump to a higher quantum state, the atom must receive energy from the outside world. A freeelectron laser consists of an electron beam propagating through a periodic magnetic field. 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 freeelectron laser at stanford university today 22 freeelectron lasers operating worldwide 19 fels proposed or in construction. Due to the significant changes in the electron and lattice temperature caused by highpower laser heating, g could be temperature dependent. Unexpectedly, navys superlaser blasts away a record wired. The effects on ifel acceleration with respect to the variation of the laser electric field, the input. Osa femtosecond freeelectron laser xray diffraction data. Fel 2017 will focus on recent advances in free electron laser theory, experiments, electron beam, photon beam and undulator technologies, and some applications of free electron lasers. The freeelectron laser is one of the navys highestpriority weapons programs, and its not hard to see why. How a quantum laser works an external source of energy excites electrons from the ground state to an. Hopf f, kuper t, moore g and scully m 1980 the freeelectron laser from a laserphysics perspective phys. Experimental and numerical studies of the inverse free electron laser using a gwlevel 10.
Dumping the highpower electron beam is wasteful and creates radiation hazards e dump is beam energy before the beam dump. The free electron laser fel uses a high quality relativistic beam of. The free electron laser is one of the navys highestpriority weapons programs, and its not hard to see why. The essential features of the theory of the free electron laser fel are given in some detail.
Lectures on the free electron laser theory and related topics g. Pdf highgain freeelectron laser theory, introduction. Physics freeelectron lasers trigger nuclear transitions. Sase free electron laser short pulse sase free electron laser wavelength range, nm 10. The free electron laser fel is a natural alternative as a radiation source national research council, 1982. Analytical theory of shortpulse freeelectron laser oscillators. S u trajectory length of one undulator period otherwise energy exchange cancels over many periods. The data establish the first large benchmark data sets for coherent diffraction methods freely available to the public, to bolster the development of algorithms that are essential for developing this novel approach as a useful imaging technique. In a fel the optical amplification takes place in an undulator which is fed with high energy electrons from an electron. Pdf highgain freeelectron lasers fels are being developed as extremely bright sources for a nextgeneration xray facility. Introduction to free electron lasers and fourthgeneration. Introduction to free electron lasers the nature of light gaussian beam laser beam emittance. Freeelectron laser simple english wikipedia, the free. The very first electromagnetic radiation amplifier was built with ammonia in the range of microwaves and was called maser, for microwave amplification by stimulated emission of radiation.
Synchrotron radiation sources and free electron lasers. This can happen through a variety of mechanisms such as inelastic or semielastic collisions with other atoms and absorption of energy in the form of electro. New theoretical calculations show that an xray freeelectronlaser pulse can generate transitions in excited nuclei via an indirect process involving electron capture. A free electron laser fel is a linear accelerator that is designed to produce very fast bursts of light with extremely high peak brightness. New theoretical calculations show that an xray free electron laser pulse can generate transitions in excited nuclei via an indirect process involving electron capture. Classical theory of freeelectron lasers book iopscience. The free electron laser fel will be an outstanding tool for research and industrial application. Today such lasers are used for research in materials science, chemical technology, biophysical. The optical resonator with macroscopic dimensions that could store significant optical power at short wavelengths was crucial to the invention of the laser.
The freeelectron laser is tunable and has the widest frequency range of any laser type, 3 currently ranging in wavelength from microwaves, through terahertz. Laser mode laser field laser action free electron laser moving frame these keywords were added by machine and not by the authors. This chapter provides a detailed introduction to the 1d theory of highgain free electron laser fel and a brief overview of the 3d scaling function for fel gain. A motivation and introduction b theoretical approach c. E r,t 2 em wave is faster than electron, but periodic interaction if waveelectron slippage is one wavelength per undulator period v s c u l u. The light is emitted as the electron beam bunches into many very thin. The center for free electron laser science as a joint enterprise of desy, the max planck society mpg, and the university of hamburg is designed to advance science with next generation light sources and lasers. A simplified description of xray freeelectron lasers. In this paper the physical process of new type of coherent. 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. It shares the same optical properties as conventional lasers such as emitting a beam consisting of coherent electromagnetic radiation which can reach high power.
The high gain fel based on the principle of self amplified spontaneous emission is treated on a qualitative level. A free electron laser is a generator of tunable, coherent, high power radiation from millimeter through ultraviolet wavelengths. Fels based on jefferson labs superconducting electronaccelerating technology are being developed to process plastics. Pdf introduction to the physics of free electron laser and. 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.
Pdf analytical theory of shortpulse freeelectron laser. We look forward to welcoming you to beautiful santa fe, new mexico, usa. Lectures on the free electron laser theory and related. Jefferson labs freeelectron laser is the worlds highestpower tunable infrared laser and was developed using the labs expertise in superconducting radiofrequency srf accelerators. A free electron laser fel, is a type of laser whose lasing medium consists of veryhighspeed electrons moving freely through a magnetic structure, hence the term free electron. 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. On the theory of the free electron laser springerlink. Fels make some of the most brilliant light sources ever made by humankind. Physics of the freeelectron laser lasers, photonics, and.
The freeelectron 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. The laser is a device which is today used in a wide list of fields. A freeelectron laser fel operating in the quantum regime can provide a compact and monochromatic xray source. In 1997 the navy distanced itself from supporting the freeelectron laser as a tool that could shoot. Pelligrini, introduction to the physics of the free electron laser, laser handbook, vol. Osa femtosecond freeelectron laser xray diffraction. 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. Cu, be using lcaomo, and then extends this approach. This makes it desirable to have a theoretical treatment accessible to nonspecialists and students.
In 1997 the navy distanced itself from supporting the free electron laser as a tool that could shoot. 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. We describe femtosecond xray diffraction data sets of viruses and nanoparticles collected at the linac coherent light source. Basic physical processes and principles of free electron. This graphic shows the secondary process by which xfel light can drive the energy release from a sample containing a nuclear isomer. In this thesis, however, we are dealing with a parameter regime in which quantum effects become important. A freeelectron 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. It is convenient to change the independent variable to z to get. Theory and practice of free electron lasers particle accelerator school day 1 dinh nguyen, steven russell. His current research interests include the theory and design of novel optical resonators for highresolution free electron laser spectroscopy, xray generation and highfield physics. It is a powerful and challenging combination of particle accelerator and laser physics and technology. Introduction to freeelectron lasers neil thompson astec. All present realizations of a freeelectron laser fel can be solely described by classical physics. A free electron laser fel operating in the quantum regime can provide a compact and monochromatic xray source.
An electron trajectory jj j dmv ee v b dt the lorentz force equation for the jth electron is written. The role of electronphonon coupling in ultrafast laser. Choosing the required parameters laser resonators for fels fel output characteristics fel vs conventional laser current trends. The independent variable of the electron trajectory here is t, and only t. Electron injectors chapter chapter chapter chapter chapter chapter chapter. In this article a phenomenological temperaturedependent g is introduced to simulate ultrafast laser heating in metals. The freeelectron laser fel uses a relativistic beam of electrons passing through an undulating magnetic field a wiggler to. Most of the ultrafast laser heating analysis to date has been accomplished with a constant electronphonon coupling factor g. Until recently fels have been operating at infrared or near ultraviolet wavelengths. Hopf f, kuper t, moore g and scully m 1980 the free electron laser from a laser physics perspective phys.
Free electron lasers an overview sciencedirect topics. Free electron lasers lecture i brian mcneil, university of strathclyde, glasgow, scotland. Were fast approaching the limits of our ability to hit maneuvering pieces of metal. Pdf this report is a primer introduction on the sources of coherent syncrotron radiation from fels compared to conventional lasers. If you want to obtain moving images of highspeed molecular processes at an atomic scale, one of the best facilities in the world is the xray free electron laser xfel at stanford university.
A new spectrum of opportunities for manufacturing and for basic research. Basic physical processes and principles of free electron lasers fels dagnachew w. 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. N 1 to achieve the condition of population inversion between e 2 and e 1 at moderate pumping. Each electron emits a wave train with n u cycles 1n u n u. Freeelectron lasers fels offer substantial cost and capability advantages including advantages for highvolume materials processing over other manufacturing tools. His current research interests include the theory and design of novel optical resonators for highresolution freeelectron laser spectroscopy, xray generation and. A free electron laser, or fel, is a laser that produces a very bright beam of light. The fel used operating principles to form the beam that are very different operating principles of a conventional. A freeelectron laser fel, is a type of laser whose lasing medium consists of veryhighspeed electrons moving freely through a magnetic structure, hence the term free electron. The term laser is an acronym for light amplification by.
The center for freeelectron laser science as a joint enterprise of desy, the max planck society mpg, and the university of hamburg is designed to advance science with next generation light sources and lasers the three partners join forces to explore structural changes of atoms, molecules, condensed, biological, or warm dense matter on. Moreover, tunable radiation sources are not perfectly monochromatic. In recent years the use of diodepumped solidstate dpss lasers in oem applications has been growing rapidly. Path to understanding nobel symposium on free electron laser research june 14 18, 2015 sigtuna, sweden john m. A freeelectron laser, or fel, is a laser that produces a very bright beam of light. 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. The fel also provides ultraviolet laser light, including vacuum ultraviolet light, and is also a source of terahertz light. Physics of the freeelectron laser the freeelectron laser can produce intense, coherent light as the result of the interaction between an electron beam and an electric field of light.
For example, in the ir region, a pulsed optical parametric oscillator tunable over the 1,4501,800 cm. A simple model for the nonlinear evolution of a shortpulse free electron laser oscillator in the small. Sasefreeelectron laser short pulse sasefreeelectron laser wavelength range, nm 10. Free electron lasers are laser devices where light amplification occurs by interaction with fast electrons in an undulator. Freeelectron laser an overview sciencedirect topics.
Beginning with an explanation of the basic gain mechanism, the lectures continue with a discussion. Rp photonics encyclopedia free electron lasers, fel. A high energy laser hel weapon system is an excellent candidate to fulfill this diverse role. Xray freeelectron lasers xfels are finally a reality. The spent electron beams still have 99% of the initial energy. Laser is an acronim for light amplification by stimulated emission of radiation. Free electron laser page of the world wide web virtual library this is a collection of web resources. Free electron laser fel theory is extended to explain several effects associated with high. Ron ballinger gives todays lecture, explaining how the behavior of electrons in aggregate solids determines their electrical and thermal conductivities, optical absorption, and other physical properties.
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