Magnetic phase dependency of the thermal conductivity of FeRh from thermoreflectance experiments and numerical simulations

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F24%3APU152217" target="_blank" >RIV/00216305:26620/24:PU152217 - isvavai.cz</a>

Výsledek na webu

<a href="https://journals.aps.org/prmaterials/abstract/10.1103/PhysRevMaterials.8.084411" target="_blank" >https://journals.aps.org/prmaterials/abstract/10.1103/PhysRevMaterials.8.084411</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevMaterials.8.084411" target="_blank" >10.1103/PhysRevMaterials.8.084411</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Magnetic phase dependency of the thermal conductivity of FeRh from thermoreflectance experiments and numerical simulations

Popis výsledku v původním jazyce

FeRh is well known in its bulk form for a temperature-driven antiferromagnetic (AFM) to ferromagnetic (FM) transition near room temperature. It has aroused renewed interest in its thin-film form, with particular focus on its biaxial AFM magnetic anisotropy which could serve for data encoding, and the possibility to investigate laserassisted phase transitions, with varying contributions from electrons, phonons, and magnons. In order to estimate the typical temperature increase occurring in these experiments, we performed modulated thermoreflectance microscopy to determine the thermal conductivity kappa of FeRh. As often occurs upon alloying, and despite the good crystallinity of the layer, kappa was found to be lower than the thermal conductivities of its constituting elements. More unexpectedly, given the electrically more conducting nature of the FM phase, it turned out to be three times lower in the FM phase compared to the AFM phase. This trend was confirmed by examining the temporal decay of incoherent phonons generated by a pulsed laser in both phases. To elucidate these results, first- and second-principles simulations were performed to estimate the phonon, magnon, and electron contributions to the thermal conductivity. They were found to be of the same order of magnitude, and to give a quantitative rendering of the experimentally observed kappa AFM. In the FM phase, however, simulations overestimate the low experimental values, implying very different (shorter) electron and magnon lifetimes.

Název v anglickém jazyce

Magnetic phase dependency of the thermal conductivity of FeRh from thermoreflectance experiments and numerical simulations

Popis výsledku anglicky

FeRh is well known in its bulk form for a temperature-driven antiferromagnetic (AFM) to ferromagnetic (FM) transition near room temperature. It has aroused renewed interest in its thin-film form, with particular focus on its biaxial AFM magnetic anisotropy which could serve for data encoding, and the possibility to investigate laserassisted phase transitions, with varying contributions from electrons, phonons, and magnons. In order to estimate the typical temperature increase occurring in these experiments, we performed modulated thermoreflectance microscopy to determine the thermal conductivity kappa of FeRh. As often occurs upon alloying, and despite the good crystallinity of the layer, kappa was found to be lower than the thermal conductivities of its constituting elements. More unexpectedly, given the electrically more conducting nature of the FM phase, it turned out to be three times lower in the FM phase compared to the AFM phase. This trend was confirmed by examining the temporal decay of incoherent phonons generated by a pulsed laser in both phases. To elucidate these results, first- and second-principles simulations were performed to estimate the phonon, magnon, and electron contributions to the thermal conductivity. They were found to be of the same order of magnitude, and to give a quantitative rendering of the experimentally observed kappa AFM. In the FM phase, however, simulations overestimate the low experimental values, implying very different (shorter) electron and magnon lifetimes.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20500 - Materials engineering

Projekt

—

Návaznosti

—

Rok uplatnění

2024

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

PHYSICAL REVIEW MATERIALS

ISSN

2475-9953

e-ISSN

—

Svazek periodika

8

Číslo periodika v rámci svazku

8

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

14

Strana od-do

„“-„“

Kód UT WoS článku

001302143800003

EID výsledku v databázi Scopus

2-s2.0-85203597340