Project Manager

Quintin Meier, CNRS Researcher at Institut Néel

N° ANR: 24-EXSP-0006

The MALT project (Design and Control of Altermagnetic Materials) aims to study a specific subset of altermagnets: materials that undergo displacive structural phase transitions which break symmetry, shifting from a non-altermagnetic state to an altermagnetic one. By controlling these structural distortions, it becomes possible to directly influence the altermagnetic properties.

Challenges

> Analyze the symmetry properties of various distortions and their implications for altermagnetic spin splitting, enabling the classification of materials based on symmetry consideration

> Use ab initio methods to study altermagnetic spin splitting in candidate materials.

> Explore strategies to control the order parameters governing structural transitions, in order to enable precise modulation of the altermagnetic state

Positioning the Project with the PEPR

The MALT project, focused on a new class of antiferromagnetic materials, addresses fundamental theoretical questions while fostering synergies between theory and experimentation, aligning it with the goals of TP3: SPINTHEORY.
Moreover, the altermagnetic properties studied in MALT are relevant for spintronic applications, establishing a direct connection with TP1: SPINMAT.
The project also allows the coordinator to strengthen their expertise in ab initio calculations, phase transition physics, and multiferroic materials, applied here to the emerging context of altermagnetism.

Development of the interactive tool: #MagSymMultipoles

Multipolar orders capture the characteristic spatial patterns of charge density or magnetization. They are therefore valuable for characterizing materials and their properties, such as ferroelectricity, magnetoelectricity, or altermagnetism.

This tool, MagSymMultipoles, was developed by Maxime Braun (postdoctoral researcher at Institut Néel) with the help of Taimor Yaqut (engineering student at Grenoble INP – Phelma). Starting from a crystal structure, it directly determines the electric and magnetic multipoles allowed by symmetry.

It allows you to:
> Explore ordinary, toroidal, and poloidal electric and magnetic orders;
> Compare cases with and without spin-orbit coupling (SOC);
> Identify ferroic and antiferroic order;
> Inspect the corresponding moment tensors;
> Visualize 3D textures in real space.