High Carrier Mobility in a Layered Antiferromagnet Integrated with Silicon.

Coupling various functional properties in one material is always a challenge, more so if the material should be nanostructured for practical applications. Magnetism and high carrier mobility are key components for spintronic applications but rather difficult to bundle together. Here, we establish EuAl2Si2 as a layered antiferromagnet supporting high carrier mobility. Its topotactic synthesis via a sacrificial two-dimensional template results in epitaxial nanoscale films on silicon. Their outstanding structural quality and atomically sharp interfaces are demonstrated by diffraction and microscopy techniques. EuAl2Si2 films exhibit extreme magnetoresistance and a carrier mobility of above 10,000 cm2 V-1 s-1. The marriage of these properties and magnetism makes EuAl2Si2 a promising spintronic material. Importantly, the seamless integration of EuAl2Si2 with silicon technology is particularly appealing for applications.