Extreme Ultraviolet Vortex
The far-field intensity profile of an EUV vortex beam carrying orbital angular momentum is characterized using an EUV Hartmann wavefront sensor (Imagine Optic, France), and is shown in a false-color map. The intricately intertwined, multi-ring feature originates from the contribution of long electron quantum paths during high-harmonic generation in an argon-filled gas cell. Other contributors: Eirini Papagiannouli, Laboratoire de Physique des Gaz et des Plasmas, Université Paris-Saclay, France.
—Alok K. Pandey Laboratoire de Physique des Gaz et des Plasmas, Université Paris-Saclay, France