Heat capacity and thermal conductivity of CdCr.sub.2./sub.Se.sub.4./sub. ferromagnet: Magnetic field dependence, experiment and calculations

0570401 - FZÚ 2024 RIV GB eng J - Journal Article
Ahn, Kyo-Hoon - Jirák, Zdeněk - Knížek, Karel - Levinský, Petr - Soroka, Miroslav - Beneš, L. - Zich, J. - Navrátil, J. - Hejtmánek, Jiří
Heat capacity and thermal conductivity of CdCr₂Se₄ ferromagnet: Magnetic field dependence, experiment and calculations.
Journal of Physics and Chemistry of Solids. Roč. 174, Mar. (2023), č. článku 111139. ISSN 0022-3697. E-ISSN 1879-2553
R&D Projects: GA MŠMT(CZ) EF16_019/0000760; GA MŠMT(CZ) LM2018096; GA ČR(CZ) GA19-06433S
Grant - others:OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Research Infrastructure: e-INFRA CZ - 90140
Institutional support: RVO:68378271
Keywords : CdCr₂Se₄ * ferromagnets * specific heat capacity * thermal conductivity * magnons * phonons
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 4, year: 2022
Method of publishing: Limited access
https://doi.org/10.1016/j.jpcs.2022.111139

The low-temperature specific heat capacity and thermal conductivity under magnetic field 0–13 T is investigated on polycrystalline sample of the ferromagnetic insulator CdCr2Se4, possessing spinel structure with magnetic Cr3+ ions in the octahedrally coordinated sites. The phonon (lattice) and magnon contributions are separated by their characteristic temperature dependencies and by quenching of the magnon component under high magnetic fields in the isothermal measurements. The results are analyzed with respect to formulas for model systems and confronted with ab-initio calculations of phonon and magnon spectra. The theoretical formula for the field-induced quenching of magnon heat capacity is well reproduced, but there are two kinds of deviations from expected behavior deserving attention:Heat capacity at low fields is by several percent lower than expected and approaches the theoretical curve only above ∼0.5 T.
Permanent Link: https://hdl.handle.net/11104/0341710