Spatially confined magnetic shape-memory Heuslers: Implications for nanoscale devices

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F26%3A0197793" target="_blank" >RIV/00216305:26620/26:0197793 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S1359645424009273" target="_blank" >https://www.sciencedirect.com/science/article/pii/S1359645424009273</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.actamat.2024.120579" target="_blank" >10.1016/j.actamat.2024.120579</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Spatially confined magnetic shape-memory Heuslers: Implications for nanoscale devices

Popis výsledku v původním jazyce

Magnetic shape-memory (MSM) Heuslers are among the most promising materials for thermo-magneto-mechanical applications. However, the knowledge about the martensitic transformation (which is the basis of the multifunctionality in these materials) as a function of size reduction in the submicron scale is still very limited. Here, we aim to bridge this knowledge gap by investigating the behavior of these materials upon nanoscale confinement. We customize a top-down approach by patterning arrays of submicron epitaxial Ni-Mn-Ga structures with lateral sizes down to similar to 70 nm, using a Cr hard mask on MgO(001) substrate. The structures include straight stripes, radial stripes, squares and triangles. The martensitic transformation temperature, sharpness, thermal hysteresis and magnetic characteristics of the material are investigated upon spatial confinement. Transmission electron microscopy techniques including Geometric Phase Analysis (GPA) algorithm, and quantitative theoretical analysis of stress help us to evaluate the martensitic transformation of Ni-Mn-Ga starting from continuous films and down to sub-micron patterns. We show that the size-dependent internal stress relaxation plays a primary role in broadening the martensitic transformation of the material, reducing thermal hysteresis, and pushing the transformation toward higher temperatures in the sub-micron structures. These findings highlight the importance of stress considerations upon incorporation of MSM Heusler materials into nanoscale functional devices.

Název v anglickém jazyce

Spatially confined magnetic shape-memory Heuslers: Implications for nanoscale devices

Popis výsledku anglicky

Magnetic shape-memory (MSM) Heuslers are among the most promising materials for thermo-magneto-mechanical applications. However, the knowledge about the martensitic transformation (which is the basis of the multifunctionality in these materials) as a function of size reduction in the submicron scale is still very limited. Here, we aim to bridge this knowledge gap by investigating the behavior of these materials upon nanoscale confinement. We customize a top-down approach by patterning arrays of submicron epitaxial Ni-Mn-Ga structures with lateral sizes down to similar to 70 nm, using a Cr hard mask on MgO(001) substrate. The structures include straight stripes, radial stripes, squares and triangles. The martensitic transformation temperature, sharpness, thermal hysteresis and magnetic characteristics of the material are investigated upon spatial confinement. Transmission electron microscopy techniques including Geometric Phase Analysis (GPA) algorithm, and quantitative theoretical analysis of stress help us to evaluate the martensitic transformation of Ni-Mn-Ga starting from continuous films and down to sub-micron patterns. We show that the size-dependent internal stress relaxation plays a primary role in broadening the martensitic transformation of the material, reducing thermal hysteresis, and pushing the transformation toward higher temperatures in the sub-micron structures. These findings highlight the importance of stress considerations upon incorporation of MSM Heusler materials into nanoscale functional devices.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20500 - Materials engineering

Projekt

—

Návaznosti

—

Rok uplatnění

2025

Kód důvěrnosti údajů

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

Název periodika

Acta materialia

ISSN

1359-6454

e-ISSN

1873-2453

Svazek periodika

284

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

11

Strana od-do

1-11

Kód UT WoS článku

001371317900001

EID výsledku v databázi Scopus

2-s2.0-85210066092