Distinguishing antiferromagnetic spin sublattices via the spin Seebeck effect

Determining the magnetic structure of antiferromagnets is a fundamental challenge for the basic understanding and development of antiferromagnetic spintronic devices. However, apart from techniques that probe individual spins in antiferromagnets directly (such as spin-polarized scanning tunneling microscopy), there are few techniques that can provide independent information for each antiferromagnetic sublattice. Here, the authors demonstrate that spin Seebeck signals from the antiferromagnetic insulator Cr${}_{2}$O${}_{3}$ are controlled by surface spins, and independently detect the orientation of the two different sublattices purely electrically.