Using a Bessel light beam as an ultrashort period helical undulator

B. C. Jiang, Q. L. Zhang, J. H. Chen, Z. T. Zhao
2017 Physical Review Accelerators and Beams  
The undulator is a critical component to produce synchrotron radiation and free electron laser. When a Bessel light beam carrying the orbit angular momentum co-propagates with an electron beam, a net transverse deflection force will be subjected to the electron beam. As a result of dephasing effect, the deflection force will oscillate acting as an undulator. For such a laser based undulator, the period length can reach sub-millimeter level, which will greatly reduce the electron energy for the required X-ray production.
doi:10.1103/physrevaccelbeams.20.070701 fatcat:43o4ybpid5hxzbz6x53bjnjxha