Description du sujet de thèse

Recently, a third type of magnetic materials, dubbed altermagnets, have been discovered in collinear antiferromagnets [1]. The specific symmetry of their spin structure gives rise to outstanding properties, gathering the advantages of ferromagnets (spin splitting - though highly anisotropic in momentum space-, finite anomalous magnetotransport and magnetooptical effects) and antiferromagnetic materials (vanishing magnetization by symmetry, ultrafast dynamics). The distinctive band structures of altermagnets makes it possible to expand core spin physics with altermagnets (giant or tunneling magnetoresistance effect for instance) and open up prospects for novel and interesting phenomena such as topological superconductivity. However, these theoretical predictions still require experimental demonstration. This is partly due to the scarcity of experimentally available materials. The SPIXY team at CINaM has pioneered the epitaxial growth of one of them (Mn5Si3) barely one year after the first predictions of altermagnet and is now developing the controlled growth of a second one (MnTe). In this context, the ANR-DFG HEXAS project tackles two main issues that are the experimental observation of (i) the tunnel magnetoresistance and spin transfer torque effects, (ii) spin polarized triplet-superconductivity in Mn-based altermagnets.
The work will be carried out within the SPIXY team at CINaM. Using molecular beam epitaxy (MBE), the candidate will have in charge the growth of dedicated heterostructures to experimentally demonstrate such effects. She/he will conduct their advanced structural, chemical and magnetic characterizations. Synchrotron experiments (such as ARPES, XMCD…) may be considered. To optimize material properties and heterostructure design, the candidate will work closely with other teams in our long-term consortium (France, Germany, Czechia - see e.g. Refs 2-6) in which transport measurements and theoretical modeling will be carried out. This complete picture will allow to unveil the underlying physical mechanisms of altermagnetic-based spintronics.

Contexte de travail

Highly motivated candidates in experimental physics with a Master degree (or equivalent) in condensed matter physics or materials science. A prior experience in physical or chemical vapor deposition growth would be appreciated. A strong involvement in the maintenance of the MBE chamber will be expected. Qualities such as pragmatism, professionalism, taste for teamwork, but also autonomy are expected. A good English level will be appreciated.

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

The position for which you are applying is in a sector by the protection of scientific and technical potential PPST and therefore requires, in accordance with regulations, that your arrival be authorized by the competent authority.