Symmetry-breaking induced surface magnetization in nonmagnetic RuO 2

作者：Dai Q. Ho, D. Quang To, Ruiqi Hu, Garnett W. Bryant, Anderson Janotti · 发表于：Physical Review Materials · 年份：2025 · DOI：10.1103/6fxv-153y · 被引用次数：7 · 研究领域：Advanced Condensed Matter Physics、Magnetic properties of thin films、Magnetic and transport properties of perovskites and related materials

Altermagnetism, a collinear magnetic phase distinct from ferro- and antiferromagnetism, has drawn attention with RuO₂ as a leading candidate. While theory predicted sizable Ru local moments driving antiferromagnetic order, a growing pile of experiments suggests that the bulk is essentially nonmagnetic, consistent with delocalized 4$d$ electrons and metallic screening. In this study, the authors reveal that the RuO₂(110) surface breaks this trend: symmetry breaking at the surface induces electronic redistribution and spontaneous magnetization. This surface magnetism produces spin-polarized states, distinctive scanning probe signatures, and potential spin-dependent transport, underscoring how subtle surface effects can radically alter the magnetic character of a nominally nonmagnetic material.