@article{455b0038c4c847b8a0d5a610806fb002,
title = "Collective excitations in the tetravalent lanthanide honeycomb antiferromagnet Na2Pr O3",
abstract = "Thermomagnetic and inelastic neutron-scattering measurements on Na2PrO3 are reported. This material is an antiferromagnetic honeycomb magnet based on the tetravalent lanthanide Pr4+ and has been proposed to host dominant antiferromagnetic Kitaev interactions. These measurements reveal magnetic fluctuations in Na2PrO3 below an energy of 2 meV as well as crystal-field excitations around 230 meV. The latter energy is comparable to the scale of the spin-orbit interaction and explains both the very small effective moment of around 1.0μB per Pr4+ and the difficulty to uncover any static magnetic scattering below the ordering transition at TN= 4.6 K. By comparing the low-energy magnetic excitations in Na2PrO3 to those of the isostructural spin-only compound, Na2TbO3, a microscopic model of exchange interactions is developed that implicates dominant and surprisingly large Heisenberg exchange interactions J≈1.1(1) meV. Although antiferromagnetic Kitaev interactions with K≤0.2J cannot be excluded, the inelastic neutron-scattering data of Na2PrO3 is best explained with a Δ=1.22 easy-axis XXZ exchange anisotropy.",
author = "Daum, {M. J.} and A. Ramanathan and Kolesnikov, {A. I.} and S. Calder and M. Mourigal and {La Pierre}, {H. S.}",
note = "Publisher Copyright: {\textcopyright} 2021 American Physical Society.",
year = "2021",
month = mar,
day = "12",
doi = "10.1103/PhysRevB.103.L121109",
language = "English",
volume = "103",
journal = "Physical Review B",
issn = "2469-9950",
publisher = "American Physical Society",
number = "12",
}