Low magnon damping of a EuSe film down to millikelvin temperatures
Abstract
The rapid development of quantum magnonics over the past decade has created a demand for magnetic materials that keep their magnon losses low at millikelvin temperatures and add functionality beyond that of the established iron garnets and ferromagnetic metals. The europium chalcogenides are natural candidates − they are magnetic semiconductors whose moment of 7 μB per Eu2+ ion stems from a half-filled 4f shell with zero orbital momentum, so that spin-orbit coupling and intrinsic damping are expected to be weak. Here we characterize an epitaxial film of the metamagnet EuSe on diamagnetic BaF2 by magnetometry and broadband ferromagnetic resonance from 10 K down to 30 mK. EuSe combines a saturation magnetization of 1100 kA/m with antiferromagnetic, ferrimagnetic and ferromagnetic phases that are reached with fields below 0.25 T. In contrast to a Gilbert-damped ferromagnet, the linewidth of the field-aligned film decreases with increasing frequency and field, and below 750 mK it no longer depends on temperature. At 30 mK, 68 GHz and 1.8 T, it reaches 5.5 mT, close to the values of bulk single crystals, which corresponds to a magnon lifetime of 2 ns and to an upper bound of 1.1×10−3 for the Gilbert damping parameter. These properties make EuSe and the europium chalcogenides promising materials for hybrid quantum systems and quantum magnonics.
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BibTeX
@misc{serha2026magnon,
title = {{Low magnon damping of a EuSe film down to millikelvin temperatures}},
author = {Rostyslav O. Serha and Jan Hofer and Khrystyna O. Levchenko and Andreas Ney and Sergej O. Demokritov and Gunther Springholz and Andrii V. Chumak},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.21733},
eprint = {2610.21733},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.21733},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Low magnon damping of a EuSe film down to millikelvin temperatures
AU - Rostyslav O. Serha
AU - Jan Hofer
AU - Khrystyna O. Levchenko
AU - Andreas Ney
AU - Sergej O. Demokritov
AU - Gunther Springholz
AU - Andrii V. Chumak
PY - 2026
DA - 2026/10/15
PB - arXiv
DO - 10.48550/arxiv.2610.21733
UR - https://arxiv.org/abs/2610.21733
AB - The rapid development of quantum magnonics over the past decade has created a demand for magnetic materials that keep their magnon losses low at millikelvin temperatures and add functionality beyond that of the established iron garnets and ferromagnetic metals. The europium chalcogenides are natural candidates − they are magnetic semiconductors whose moment of 7 μ_B per Eu^2+ ion stems from a half-filled 4f shell with zero orbital momentum, so that spin-orbit coupling and intrinsic damping are expected to be weak. Here we characterize an epitaxial film of the metamagnet EuSe on diamagnetic BaF_2 by magnetometry and broadband ferromagnetic resonance from 10 K down to 30 mK. EuSe combines a saturation magnetization of 1100 kA/m with antiferromagnetic, ferrimagnetic and ferromagnetic phases that are reached with fields below 0.25 T. In contrast to a Gilbert-damped ferromagnet, the linewidth of the field-aligned film decreases with increasing frequency and field, and below 750 mK it no longer depends on temperature. At 30 mK, 68 GHz and 1.8 T, it reaches 5.5 mT, close to the values of bulk single crystals, which corresponds to a magnon lifetime of 2 ns and to an upper bound of 1.1×10^−3 for the Gilbert damping parameter. These properties make EuSe and the europium chalcogenides promising materials for hybrid quantum systems and quantum magnonics.
ER -