Self-induced spin glass state in elemental and crystalline neodymium

Abstract

A structurally ordered spin glass Spin glasses that form in disordered materials such as magnetic alloys have locally varying magnetic patterns, and their spin relaxation occurs over time scales spanning many orders of magnitude. Kamber et al. used spin-polarized scanning tunneling microscopy to image the magnetism on the (0001) surface of thick, single-crystal films of neodymium as a function of temperature and magnetic field. Despite the lack of structural disorder, they found a spectral distribution of degenerate magnetic wave vectors, or Q states, that exhibited spatiotemporal variation. In this spin-Q glass, pockets of nearly degenerate spin spiral states formed with varying periodicity. Ab initio electronic structure coupled to atomistic spin dynamics calculations suggests that the double hexagonal closed packed crystal structure in neodymium drove strongly frustrated magnetism that created these pockets. Science , this issue p. eaay6757