Investigation of length reduction and radiation power enhancement of short-wavelength free electron laser

Document Type : Original Article

Authors

1 Plasma and nuclear fusion research school, Nuclear Science and Technology Research Institute (NSTRI)

2 Photonic and quantum technologies research school, Nuclear Science and Technology Research Institute

Abstract

Free electron laser technology is one of the most suitable options to achieve high power, coherent radiation in the range of short wavelengths, especially XUV and X. One of the most important challenges in construction of short-wavelength free electron lasers is the large dimension of the system. Therefore a significant part of free electron laser researches is concentrated on length reduction and radiation enhancement of the system. In this paper, the performance of free electron lasers in the range of XUV or soft X is investigated and some techniques for minimizing and radiation enhancement of the system are presented. For this purpose, methods such as using higher harmonics of the radiation field and pre-bunched injecting electron beam into the wiggler are proposed. To compensate for the decrease in the radiation power of the third harmonic, the wiggler tapering method was used to amplify the radiation field. Based on three-dimensional simulations performed using the MEDUSA code, it was observed that wiggler tapering can increase radiation power significantly. It was also found that using a pre-bunched electron beam can amplify saturation power and accelerate the growth process of the radiation field and thus reduce the saturation length of the free electron laser. Therefore, tapering of the wiggler field along with the beam pre-bunching method can play a very important role in length reduction and amplification of the radiation field of short-wavelength free electron laser.

Keywords


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