Fig. 1: Bethe–Slater-type exchange interaction.
From: Emergent exchange-driven giant magnetoelastic coupling in a correlated itinerant ferromagnet
a,b, Illustration of the symmetry of the wavefunction of two electrons at neighbouring sites, being spatially antisymmetric for parallel spins (a) and symmetric for antiparallel spins (b). c, Sketch of the Bethe–Slater curve showing the energy difference between the antiferromagnetic (EAFM) and ferromagnetic (EFM) configurations of a system of two electrons in atomic-like wavefunctions as a function of the distance (r) between them. The black arrow indicates the direction of the exchange force (F) for a system in the decaying part of the curve (black circle): the exchange force points towards lower r if the spins are parallel, whereas it points towards larger r if the spins are antiparallel.
