Magnetoelectric (ME) materials combine magnetization (M) and polarization (P) through cross-couplings M(E) and P(H) and provide starting materials for developing high-density data storage, spintronics and low consumption devices owing to the interplay between both properties. Modifying M or P through either a magnetic or electric field may reduce the needed energy in non-volatile memories various devices. Yet, designing such multifunctional materials is far to be straightforward owing to the phenomenological origin of both magnetism and ferroelectricity which tends to exclude each other. In addition, one of the key questions for future development concerns the mutual coupling between both properties in order to be able to control one property by the other.
While the wide majority of ME materials belong to metal oxides, we propose to investigate an original family of ME molecular materials which have been poorly investigated for such purpose.
MEMORI is a multidisciplinary fundamental research project at the crossroad of different disciplines involving coordination and materials chemistries and physical studies with the aims to design and investigate new and original ME molecular materials exhibiting strong coupling between both properties. Up to now, the in-depth study of the electric properties of molecular materials appears quite difficult since dense samples (large single-crystals) are required to obtain reliable data. This requires engineering and developing new methodologies that are specifically dedicated to such fragile materials. Therefore, our proposal intends to bring important breakthroughs for investing the ferroelectric properties in such materials, understanding the parameters affecting ferroelectricity up to the investigation of the synergy between magnetism and ferroelectricity.
We expect to give the proof that such molecular materials could be used to conceive systems in which the information is stored as electrically detectable but controllable by magnetism. In a more general context, we would like to demonstrate that molecular materials can be competitive in terms of properties such as ferroelectricity, with metal oxides, allowing them to be finally considered as potential candidates for future applications.
The MEMORi proposal aims to design multifunctional ME molecular materials exhibiting strong ME coupling with two main objectives:
i) The chemical design of molecular ferroelectric paramagnets of high chemical robustness based on the association between lanthanide ions and chiral Schiff base ligands. Efforts will be given to engineer systems exhibiting a high dielectric Tc or decomposition temperature with various shaping methods (single-crystals, molecular ceramics and thin films) that could eventually find subsequent applications. A specific stress will be given to develop methodologies to efficiently characterize the electric properties in order to comprehend the origins of the ferroelectricity in molecular complexes.
ii) Experimentally evidence the synergy and coupling between the magnetic and dielectric properties. Namely we expect to give the proof-of-concept that such strong interplay could be used to conceive device applications where stored-information is electrically detectable but controllable by magnetism and vice versa. Such results would represent a major breakthrough in the field of molecular and more generally in solid-state materials.
This proposal relies on strong expertises between two partners (ICGM and ICMCB) involving coordination and materials chemistry, molecular magnetism and ferroelectricity. This proposal goes all the way from the synthesis of the targeted molecular materials, their shaping in various forms, the fine understanding of their ferroelectric properties by various approaches, to the study of the ME coupling.
Monsieur Jérôme LONG (Institut de chimie moléculaire et des matériaux - Institut Charles Gerhardt Montpellier)
L'auteur de ce résumé est le coordinateur du projet, qui est responsable du contenu de ce résumé. L'ANR décline par conséquent toute responsabilité quant à son contenu.
ICMCB INSTITUT DE CHIMIE DE LA MATIERE CONDENSEE DE BORDEAUX
ICGM Institut de chimie moléculaire et des matériaux - Institut Charles Gerhardt Montpellier
Aide de l'ANR 433 285 euros
Début et durée du projet scientifique : janvier 2020 - 48 Mois