ABSTRACT

Shaping ultraviolet (UV) laser beams is critical for optimizing photoinjector performance in free-electron lasers (FELs). Simulations have shown that a 50% truncated Gaussian beam can achieve the lowest emittance via space charge compensation. However, conventional shaping techniques are limited by significant power losses or are not adapted for UV light.

In this talk, we’ll explore advanced laser beam shaping techniques and their impact on photoinjector performance. We’ll discuss a novel approach to transverse beam shaping using phase plates. This method enables precise UV beam shaping while minimizing power loss. We will discuss simulations guiding the design of these optics and the practical steps toward their fabrication. Additionally, we will examine the reverse problem of beam purification, where a conical spatial filter is used to refine the laser mode to TEM00.