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Orbital mixing and strong Hund's coupling stabilize spin order in the van der Waals ferromagnet CrI3

A. De Vita1,2,*, S. Stavrić3,†, R. Sant4,5, N. B. Brookes4, I. Vobornik6, G. Panaccione6, S. Picozzi7,8, M. Wolf2, L. Rettig2 et al.

R. Ernstorfer1,2,‡ and T. Pincelli1,2,§

  • *Contact author: alessandro.de.vita@tu-berlin.de
  • †Contact author: stavric@vin.bg.ac.rs
  • ‡Contact author: ernstorfer@tu-berlin.de
  • §Contact author: pincelli@tu-berlin.de
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Phys. Rev. B 113, 205120 – Published 8 May, 2026

DOI: https://doi.org/10.1103/bdbj-98tj

Abstract

Recent years have seen a vast increase in research into van der Waals magnetic materials. In many of these systems, magnetism is introduced via light 3d transition metal elements, combined with chalcogenides or halogens. Despite the great technological promise in the field of spintronics, the connection between the d-orbital configuration and the occurrence of low-dimensional magnetic order is currently unclear. Here we address the prototypical two-dimensional ferromagnet CrI3, via complementary spectroscopies and density functional theory calculations. We reveal the electronic structure and orbital character of bulk CrI3 in the paramagnetic and ferromagnetic phases, describing the couplings underpinning its energy diagram, and providing a robust experimental demonstration that the stabilization of ferromagnetism is attributable to orbital mixing between I p and Cr eg states, and to the presence of strong Hund's coupling. These findings reveal the microscopic connection between orbital and spin degrees of freedom, providing fundamental insights into the behavior of low-dimensional magnetic materials.

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Phys. Rev. B 113, 205120– Published 8 May, 2026
  • Received 12 January 2026
  • Revised 27 March 2026
  • Accepted 7 April 2026
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