The free electron laser was invented by john madey in 1971 at stanford university. 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 possibility of terawatt tw xray freeelectron lasers xfels has been discussed using novel superconducting helical undulators. However, formatting rules can vary widely between applications and fields of interest or study. High harmonic generation in the undulators for free electron. 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. We study the characteristics of the electron motion. Short period, high field undulators can enable short wavelength free electron lasers fels at low beam energy, with decreased gain length, thus allowing much more compact and less costly fel systems. Development of miniundulators for a tabletop freeelectron. Single shot polarization characterization of xuv fel.
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. Aug 20, 2006 in later developments, stemming from this, single pass gain of circularly polarized radiation was experimentally demonstrated by means of a twister structure and an optical cavity, obtained by adding mirrors to the magnet assembly, was used to achieve buildup of the radiation in an oscillator device known as the freeelectron laser. Pedersen danfysik as taastrup, denmark abstract danfysik has produced insertion devices for the fel community for almost 10 years. The freeelectron laser fel principle has been known since the early 1970s but for many years fels have played a marginal role in comparison with conventional lasers. Insertion devices for free electron lasers oxford scholarship. The first sources of powerful coherent radiation were the microwave tubes invented earlier in this century. This article outlines the early development of the undulator in which an electron beam travelling through a system of magnetic fields with directions. This option allows users to search by publication, volume and page selecting this option will search the current publication in context. However, the use of conventional undulators using permanent magnets also implies system sizes which are large. Numerous and frequentlyupdated resource results are available from this search. Today such lasers are used for research in materials science, chemical technology, biophysical science, medical applications, surface studies, and solidstate physics. Statistical and coherence properties of radiation from xray. An undulator is an insertion device from highenergy physics and usually part of a larger installation, a synchrotron storage ring, or it may be a component of a free electron laser. However, an important step in fel development came in 1976 when madey and his coworkers at stanford university measured gain from an fel configured as an amplifier at 10.
This new reference is the first fully selfcontained and unified monograph on the design and operation of undulators and freeelectron lasers. In modern highgain freeelectron lasers, ultrafast photon pulses designed for studying. Statistical and coherence properties of radiation from xray freeelectron lasers this article has been downloaded from iopscience. Lasers based on electrons that are bound to atomic or molecular energy levels operate. It consists of a periodic structure of dipole magnets.
A gaussian expansion is used for freespace propagation, and an expansion in waveguide modes for fully guided propagation, or a combination of the two for partial guiding at thz frequencies. Threedimensional, timedependent simulation of freeelectron. Advanced undulator concepts for future freeelectron lasers. We study the characteristics of the electron motion in this type of undulators and analyze the spectral properties of the emitted radiation. The concept of comptontype freeelectron lasers fels operating in short wavelength ranges with a high efficiency and power level is currently underway at the iap ras nizhny novgorod. Introduction to free electron lasers and fourthgeneration light. We also derive general expressions for the small signal gain coefficient and for the saturation intensity. A new code under development, named minerva, uses a modal expansion for the optical field. Towards a free electron laser based on laser plasma.
The free electron laser fel principle has been known since the early 1970s but for many years fels have played a marginal role in comparison with conventional lasers. Xray free electron lasers slac national accelerator. In later developments, stemming from this, single pass gain of circularly polarized radiation was experimentally demonstrated by means of a twister structure and an optical cavity, obtained by adding mirrors to the magnet assembly, was used to achieve buildup of the radiation in an oscillator device known as the freeelectron laser. Lidia, light sources and free electron lasers, slide 7. Threedimensional, timedependent simulation of freeelectron lasers with planar, helical, and elliptical undulators h. There are conceptual designs for much less expensive soft xray fels using sheared pulses from table top terawatt t 3 lasers as optical undulators. Operation of a freeelectron laser from the extreme ultraviolet to the water window, nature photon. In this paper, we describe two recent undulator deliveries. 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. It will be of use to all those working in freeelectron laser research as well as for physicists and graduate students who need an introduction to. Free electron lasers lecture i brian mcneil, university of strathclyde, glasgow, scotland. This concept is aimed at reducing the energy of a driving relativistic electron beam and thereby increasing the efficiency of the electronwave interaction in fels, as well as.
Free electron lasers with higher average power and shorter wavelengths are under development. This chapter looks at these different requirements and discusses how they are implemented in practice. This book is a reference text for all those working in freeelectron laser research as well as being a learning aid for physicists and graduate students who wish an introduction to this field. Introduction high power microwave fields propagating in a waveguide can be used as undulators for freeelectron lasers fels. Contrary to most lasers, the motion of an electron in the fel may be described by classical mechanics and classical electrodynamics. After an overview of early developments and general principles of operation, the different models that can be used to describe free electron lasers are presented, organized according to their range of applicability.
Reliable information about the coronavirus covid19 is available from the world health organization current situation, international travel. Using h the minerva simulation code, an extensive steadystate analysis has been conducted. Xband microwave undulators for short wavelength free. Polarization control is a key feature of light generated by shortwavelength freeelectron lasers. The purpose of this book is to give a description of the state of the art in theoretical and experimental work achieved in radiation source development. In this work, we report the first experimental characterization of. Optical undulators for free electron lasers james lawler, joseph bisognano, robert bosch, michael green, kenneth jacobs, deniz yavuz, univ of wisconsin, madison free electron lasers fels in the xray region are opening new research directions in amo physics and other. We present the test results of a novel microwiggler structure 1 for free electron lasers, in which, each 2. A freeelectron laser that emits xrays with a wavelength of the size of an atom about. Free electron lasers operating with variably polarization. Synchrotron radiation can be generated in undulators alternating dipoles with k 1 or single. Lasers, freeelectron 3 undulator electron beam optical cavity mirror partial mirror radiation field outcoupled field fig. A primer on the physics of freeelectron lasers presented to the aps midatlantic senior physicists group college park, md 17 october 2017 henry freund.
A free electron laser consists of an electron beam propagating through a periodic magnetic field. Statistical and coherence properties of radiation from x. Undulator technologies for future free electron laser. The development of laser wakefield accelerators lwfa over the past several years has led to an interest in very compact sources of xray radiation such as tabletop free electron lasers. Pdf a freeelectron laser consists of an electron beam propagating through a.
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. Us particle acceus particle accelerator school 2009lerator school 2009 university of new mexico albuquerque nm course content 1. Because of the lack of suitable nonlinear materials, techniques for generating tunable light using commercial laboratory lasers are not effective at. It will be of use to all those working in freeelectron laser research as well as for physicists and graduate students who need an introduction to the field. Free electron laser performance within the eupraxia facility mdpi. Arthur n chester the volume contains the proceedings of the 7th course on physics and technology of free electron lasers of the international school of quantum electronics, which was held in erice italy from 17 to.
Lidia, light sources and free electron lasers, slide 3 no sources due to material losses gain discrete lines, not widely tunable. Peak brilliance of xray fels and undulators for spontaneous radiation at the. The undulator shown is a permanentmagnet planar undulator. Compactness of quantum fels arises from the use of laser pulses as optical undulators 1116. Proposal for an xray free electron laser oscillator arxiv.
Paper open access threedimensional, timedependent simulation of free electron lasers with planar, helical, and elliptical undulators to cite this article. These can be permanent magnets or superconducting magnets. Only in recent years it has become clear that these devices have the potential of becoming exceedingly powerful light sources in the vacuumultraviolet vuv and x ray regime. Their development received a strong impetus from radar development during world war ii. Highbrightness xray freeelectron laser with an optical.
Madey invented the free electron laser fel, in 1971. Aug 28, 2015 polarization control is a key feature of light generated by shortwavelength free electron lasers. We discuss the properties of free electron lasers fel operating with variably polarizing undulators. Abeamofelectrons is generated in the electron accelerator and then passed through a region ofalternating direction magnetic field wiggler. This new reference is the first fully selfcontained and unified monograph on the design and operation of undulators and free electron lasers. Care mustbe given to generating, focusing, and tiansporting the electron beam, as. In fact fel is based on the stimulated emission of virtual photons by a relativistic electron beam, passing through an undulatorwiggler, much like conventional. Free electron lasers operate on the principle of electromagnetic instability involving three components. These tubes are still successful and useful sources of. Mar 12, 2020 the concept of comptontype freeelectron lasers fels operating in short wavelength ranges with a high efficiency and power level is currently underway at the iap ras nizhny novgorod. Rp photonics encyclopedia free electron lasers, fel. We present the test results of a novel microwiggler structure 1 for freeelectron lasers, in which, each 2. Single shot polarization characterization of xuv fel pulses. Charles brau, free electron lasers academic press, 1990.
Free electron lasers are laser devices where light amplification occurs by interaction with fast electrons in an undulator. Threedimensional, timedependent simulation of freeelectron lasers with planar. Free electron lasers fels are lasers which utilize the phenomenon of stimulated undulator radiation. Free electron lasers fels in the xray region are opening new research directions in amo physics and other fields, but beam time is quite limited at these expensive facilities.
The synchrotron radiation of relativistic electrons in undulator magnets and the lowgain freeelectron laser fel are discussed in some detail. It will be of use to all those working in free electron laser research as well as for physicists and graduate students who need an introduction to the field. Only a basic understanding of relativistic mechanics and electromagnetism is presupposed. We study the characteristics of the electron motion in this type of undulators and analyze. Freeelectron lasers with higher average power and shorter wavelengths are under. In addition to making a comparison with conventional lasers, a couple of special topics concerning nearfield and cavity electrodynamics, compact and tabletop arrangements and strong radiation induced exotic states of.
Pdf introduction to the physics of free electron laser and. Novel radiation sources using relativistic electrons. Ivanyushenkov, short period undulators for storage rings and free electron lasers, journal of physics. Short period undulators for storage rings and free electron lasers article pdf available in journal of physics conference series 4253. In an fel the kinetic energy of a relativistic electron beam serves as the source of free energy to be converted to electromagnetic radiation in the undulator magnet. Introduction to the physics of the free electron laser.
Principles of coherent xray generation synchrotron. Threedimensional, timedependent simulation of free. The free electron laser utilizes technology developed by hans motz and his coworkers, who built an undulator at stanford in 1953, using the wiggler magnetic configuration which is one component of a free electron laser. Introduction creating matter from the vacuum, taking an atomic scale motion picture of a chemical. Synchrotron radiation can be generated in undulators alternating dipoles with k 1 or single dipole magnets. Undulators and freeelectron lasers book, 1990 worldcat. Selecting this option will search all publications across the scitation platform selecting this option will search. This concept is aimed at reducing the energy of a driving relativistic electron beam and thereby increasing the efficiency of the electronwave interaction in fels, as well as making the oscillator.
Statistical and coherence properties of radiation from xray free electron lasers this article has been downloaded from iopscience. In this work, we report the first experimental characterization of the polarization properties of. Outline xray free electron lasers ultrafast photon science wigglers, undulators and coherent radiation overview of an xray free electron laser selfamplified spontaneous emission sase free electron laser seeding schemes. The volume contains the proceedings of the 7th course on physics and technology of free electron lasers of the international school of quantum electronics, which was held in erice italy from 17 to 29 august 1980, under the auspices of the ettore majorana centre for scientific culture.
Coherent light is generated and contained in an optical cavity defined bythe mirrors. High harmonic generation in the undulators for free electron lasers. Pdf short period undulators for storage rings and free. Physics of freeelectron lasers introduction dinh c. A relativistic electron beam a magnetic undulator k freeelectron 3 undulator electron beam optical cavity mirror partial mirror radiation field outcoupled field fig. It summarizes clearly and comprehensibly, the basic physical aspects needed to understand the phenomena, and also provides the interested reader. Therefore, fels belong to the family of vacuum electronic devices, such as traveling wave tubes or klystrons. Free electron lasers consists of 10 chapters, which refer to fundamentals and design of various free electron laser systems, from the infrared to the xuv wavelength regimes. At present, light sources based on freeelectron laser fel facilities offer. The book includes a convenient overview of early developments and general.
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