Atomistic spin dynamics and spectroscopic investigation of spin-induced magnetoelectric multiferroic materials

Projektbeschreibung

Neuartige multiferroische Materialien mit verbesserten Eigenschaften

Werden magnetische Eigenschaften durch ein elektrisches Feld manipuliert, so handelt es sich um eine einfache, kostengünstige und energetisch nachhaltige technische Strategie. In magnetoelektrisch-multiferroischen Materialien können Ferromagnetismus und Ferroelektrizität kombiniert auftreten. Sie sind daher starke Kandidaten für verschiedene Hybrid-Anwendungen in den Bereichen Sensorik sowie Energie- und Datenspeicherung. Das Hauptziel des EU-finanzierten Projekts EMAGICS besteht darin, das Zusammenspiel elektrischer und magnetischer Eigenschaften in einphasigen Verbindungen zu erforschen und es durch Weiterentwicklung zu optimieren. Zu diesem Zweck wird das Forschungsteam eine ganze Reihe von Verbindungen, die Nickel, Mangan oder Kobalt enthalten, als Übergangsmetall untersuchen. Dabei kommen Spektroskopie und computergestützte Spindynamikanalyse zum Einsatz.

Ziel

Magnetoelectric (ME) multiferroics (MFs), materials that can combine ferromagnetism and ferroelectricity, are strong candidates for a wide range of novel hybrid technological applications, such as sensing, energy harvesting, data storage, magnonics, and spintronics, to name a few. Most importantly, the ability to manipulate the magnetization by electric fields leads to simple, cost-effective and energetically sustainable technological strategies. Despite the great efforts of the MF scientific community, the origin of the ME coupling in a series of MF materials still remains ambiguous. Experimental findings may frequently be inconclusive and misinterpreted; therefore a solid theoretical approach is essential for developing further insights in the fundamental physics hidden behind magnetoelectricity.
Ni3TeO6 champions both the static and dynamical ME effects among the single-phase MFs. In pursuit of new spin-induced MFs, resembling the celebrated Ni3TeO6, we propose the investigation of a series of compounds of the form M3TeO6 (M=Ni, Mn, Co), with a combination of mixed-valence transition metal anions on the M-site, by employing a combination of first principles calculations of spin dynamics together with experimental spectroscopic investigation.
The researcher has experience in spectroscopic techniques for ME MFs, background in first principles calculations, and aims at training in the field of first principles calculations for spin dynamics. The supervisor Prof. Sanvito is an expert in ab initio predictions with atomistic spin dynamics.
EMAGICS’ target is to unveil the underlying mechanisms that lead to the enhancement of the ME MF properties, as well as possibly increase the critical temperatures in favour of the applications. Thereafter, EMAGICS will be able to propose the synthesis of new compounds of the family M3TeO6, with a combination of mixed-valence transition metal anions on the M-site, and experimentally explore possible MF performance.