Missions

FeRh is a binary alloy that exhibits a first-order phase transition from an antiferromagnetic state to a ferromagnetic state around ~350 K. This transition is accompanied by a significant change in entropy, structure, and electrical properties, making it a key candidate for magnetocaloric effects and thermomagnetic devices. The objective is to better understand these transitions when they are thermally induced.

Activités

The candidate will use experimental equipment developed and implemented as part of recent work by the SATIE and INSP teams to study and model phase transitions. In particular, they will use thermal, magnetic, and optical characterization devices to probe the transition under different excitation conditions (temperature, magnetic field, optical excitation). These measurements will be used to feed physical models describing the dynamics of phase transition, hysteresis phenomena, and out-of-equilibrium effects, taking into account the couplings between thermal, structural, and magnetic degrees of freedom.

Compétences

Solid state physics/materials Solid foundations in condensed matter physics Knowledge of phase transitions, particularly first-order transitions Basic knowledge of magnetism (AF/FM, hysteresis, thermomagnetic couplings) Sensitivity to out-of-equilibrium effects and irreversibility phenomena Experimental techniques Experience (or strong interest) in experimental characterization Use of measuring devices: temperature control (cryostat, heating plates) magnetic fields optical techniques (reflectivity, lasers, lock-in, modulation) Ability to operate complex equipment and understand its experimental limitations Noise processing, hysteresis analysis, repeatability of measurements

Contexte de travail

Materials exhibiting first-order phase transitions are of great interest due to the sudden changes in their physical properties (magnetic, structural, electrical, or optical), opening the door to numerous technological applications. Among them, the FeRh alloy is a model system, characterized by an antiferromagnetic ↔ ferromagnetic transition close to room temperature, accompanied by strong thermal hysteresis and irreversibility phenomena. This transition results from complex couplings between thermal, magnetic, and structural degrees of freedom, the detailed understanding of which remains a fundamental challenge.

Le poste se situe dans un secteur relevant de la protection du potentiel scientifique et technique (PPST), et nécessite donc, conformément à la réglementation, que votre arrivée soit autorisée par l'autorité compétente du MESR.

Contraintes et risques

Nothings