Learn About Our Banner Image

Spin-polarized low-energy electron microscopy (SPLEEM) is a technique that allows for the direct observation of the magnetic structure of surfaces and in thin films. This SPLEEM image shows atomic terraces on the (110) surface of a tungsten crystal. It was acquired using a novel spin‑polarized, pulsed electron source triggered by an ultrafast laser, enabling magnetic imaging with unprecedented temporal resolution. Cycles of oxygen exposure followed by high-temperature flash annealing produce atomically clean W(110) surfaces. Repeated annealing cycles can cause atomic terraces to migrate across the surface. While terraces are often wide and straight, occasionally they can clump together and produce dramatic bunches and plateaus, as seen in this image. W(110) is a common substrate for SPLEEM studies because of the development of this robust, reproducible surface preparation method which enables high-quality epitaxy of ferromagnets such as Fe, Co, and rare earth elements. These systems serve as canonical platforms for magnetic domain and spin-reorientation experiments. The image was contributed to the 2025 NanoArt competition submitted by Usama Choudhry.