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arXiv · 1811.06553

$ab$-$initio$ Approaches for Low-Energy Spin Hamiltonians

Kira Riedl·Ying Li·Roser Valenti·Stephen M. Winter
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Abstract

Implicit in the study of magnetic materials is the concept of spin Hamiltonians, which emerge as the low-energy theories of correlation-driven insulators. In order to predict and establish such Hamiltonians for real materials, a variety of first principles $ab$-$initio$ methods have been developed, based on density functional theory and wavefunction methodologies. In this review, we provide a basic introduction to such methods and the essential concepts of low-energy Hamiltonians, with a focus on their practical capabilities and limitations. We further discuss our recent efforts toward understanding a variety of complex magnetic systems that present unique challenges from the perspective of $ab$-$initio$ approaches.

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Kira Riedl, Ying Li, Roser Valenti, Stephen M. Winter. 2018-11-15. $ab$-$initio$ Approaches for Low-Energy Spin Hamiltonians. https://doi.org/10.1002/pssb.201800684

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