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Origin of the magnetic ground state of Tb2Ir2O7

Y. Alexanian1,2,*, E. Lhotel1, J. Robert1, S. Petit3, E. Lefrançois1, P. Lejay1, A. Hadj-Azzem1, F. Damay3, J. Ollivier2 et al.

B. Fåk2, S. De Brion1, R. Ballou1, and V. Simonet1,†

  • *Contact author: yann.alexanian@neel.cnrs.fr
  • †Contact author: virginie.simonet@neel.cnrs.fr
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Phys. Rev. Research 8, 043060 – Published 16 October, 2026

DOI: https://doi.org/10.1103/x6n8-hz3k

Abstract

Magnetic-rare-earth pyrochlore iridates exhibit a rich variety of unconventional phases, driven by the complex interactions within and between the rare-earth and the iridium sublattices. In this study, we investigate the peculiar magnetic state of Tb2Ir2O7, where a component of the Tb3+ moment orders perpendicular to its local Ising anisotropy axis. By means of neutron diffraction and inelastic neutron scattering down to dilution temperatures, complemented by specific heat measurements, we show that this intriguing magnetic state is fully established at 1.5K and we characterize its excitation spectrum across a broad range of energies. Our calculations reveal that bilinear interactions between Tb3+ ions subjected to the Ir molecular field capture several key features of the experiments, but need to be supplemented to fully reproduce the observed behavior.

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Phys. Rev. Research 8, 043060– Published 16 October, 2026
  • Received 2 January 2026
  • Accepted 28 July 2026
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