X-ray Orbital Angular Momentum from Artificial Antiferromagnets containing Edge Dislocations*

Artificial spin lattices (ASLs), including artificial spin ices, consist of patterned magnetic nanostructures that mimic Ising spins. Here we show that a permalloy, square ASL with a double edge dislocation exhibits an ordered antiferromagnetic ground state, unlike square ASLs with a single dislocation.¹ We demonstrate that soft x-rays resonantly scattered from this magnetic texture carry orbital angular momentum. Moreover, x-ray OAM from these samples can be modulated using and temperature and applied magnetic fields. X-ray beams carrying orbital angular momentum (OAM) have potential applications in nanoscale imaging, spectroscopy, and manipulation, but current means of generating x-ray OAM are difficult to modulate or reconfigure.² Scattering from ASLs may offer a potential path to flexible control of x-ray OAM.

¹ Drisko et al. Topological frustration of artificial spin ice, Nature Communications (2017).
² Lee et al., Laguerre–Gauss and Hermite–Gauss soft X-ray states generated using diffractive optics, Nature Photonics (2019).