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arXiv · 1707.08448

Spatial Control of Photoemitted Electron Beams using a Micro-Lens-Array Transverse-Shaping Technique

A. Halavanau·G. Qiang·G. Ha·E. Wisniewski·P. Piot·J. G. Power·W. Gai
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Abstract

A common issue encountered in photoemission electron sources used in electron accelerators is the transverse inhomogeneity of the laser distribution resulting from the laser-amplification process and often use of frequency up conversion in nonlinear crystals. A inhomogeneous laser distribution on the photocathode produces charged beams with lower beam quality. In this paper, we explore the possible use of microlens arrays (fly-eye light condensers) to dramatically improve the transverse uniformity of the drive laser pulse on UV photocathodes. We also demonstrate the use of such microlens arrays to generate transversely-modulated electron beams and present a possible application to diagnose the properties of a magnetized beam.

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A. Halavanau, G. Qiang, G. Ha, E. Wisniewski, P. Piot, J. G. Power, W. Gai. 2017-07-24. Spatial Control of Photoemitted Electron Beams using a Micro-Lens-Array Transverse-Shaping Technique. https://doi.org/10.1103/physrevaccelbeams.20.103404

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