2017/08/31 by Tatsuya Shishidou, T. Shishidou, D. F. Agterberg +3 · 24 citations
Materials Science · Physics and Astronomy · #Antiferromagnetism #Electronic and Structural Properties of Oxides #Electronic structure #Fermi Gamma-ray Space Telescope #Ground state #Iron-based superconductors research #Paramagnetism #Quantum #Quantum fluctuation #Spin (aerodynamics) #Superposition principle #Topological Materials and Phenomena #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1038/s42005-018-0006-7
published in Communications Physics 1(1) (Nature Portfolio) · 7 pages, 3 figures
arxiv created 2017/09/13 · openalex created_date 2017/09/15 · openalex publication_date 2018/02/22 · arxiv updated 2018/03/13 · openalex updated_date 2026/08/06
Abstract The electronic structure of single-layer FeSe films on SrTiO 3 presents a quandary: experimentally there is no long-range magnetic order, but the observed bands are reasonably well described by density functional calculations assuming the checkerboard antiferromagnetic (CB-AFM) ordering despite this configuration not being the calculated ground state. Here we investigate the paramagnetic nature of this system via first-principles spin-spiral calculations. Fits of the spin-spiral dispersion to spin models place this S = 1 spin system in a region of parameter space where CB-AFM quantum fluctuations lead to a magnetically disordered paramagnetic state. Modeling the paramagnetic state as an incoherent superposition of spin-spiral states arising from thermal and/or quantum fluctuations, the resulting electronic bands around the Fermi level are found to closely resemble those of the ordered CB-AFM configuration, thus providing a consistent explanation of the angle-resolved photoemission observations. These results suggest that CB-AFM fluctuations play a more important role than previously thought.