Spontaneous Appearance of Low-dimensional Magnetic Electron System on Semiconductor Nanostructures

We find that spin-polarized ground states emerge in nanofacets which are self-organized on SiC (0001) surfaces. Our large-scale density-functional calculations reveal that the nanofacet formed by bunching of single bilayer steps generates peculiar carbon dangling bond states localized at but extended along step edges. The flat-band characteristics of those C states cause either ferromagnetic or anti-ferromagnetic chains on covalent semiconductors.