Uijttewaal, Matthe A.; Hickel, Tilmann; Neugebauer, Jörg; Gruner, Markus Ernst; Entel, Peter:
Understanding the phase transitions of the Ni2MnGa magnetic shape memory system from first principles
2009
In: Physical review letters, Jg. 102 (2009), Heft 3, S. 035702
Artikel/Aufsatz in Zeitschrift / Fach: Physik
Zentrale wissenschaftliche Einrichtungen » Center for Nanointegration Duisburg-Essen (CENIDE)
Titel:
Understanding the phase transitions of the Ni2MnGa magnetic shape memory system from first principles
Autor(in):
Uijttewaal, Matthe A.; Hickel, Tilmann; Neugebauer, Jörg; Gruner, Markus Ernst im Online-Personal- und -Vorlesungsverzeichnis LSF anzeigen; Entel, Peter im Online-Personal- und -Vorlesungsverzeichnis LSF anzeigen
Erscheinungsjahr
2009
Erschienen in:
Physical review letters, Jg. 102 (2009), Heft 3, S. 035702
ISSN
DOI

Abstract:

The free energies of the austenite, the (modulated) premartensite and the unmodulated martensite of Ni2MnGa are determined using density functional theory and including quasiharmonic phonons and fixed-spin-moment magnons. This approach very well reproduces the complete phase sequence (martensite<-->premartensite<-->austenite) of stoichiometric Ni2MnGa as a function of temperature. By analyzing the relevant free energy contributions, we also understand the delicate interplay of phonons and magnons driving both phase transitions.