Barre 22-23, 3e étage, pièce 317
Clément Pellet-Mary – Département de Physique, Université de Bâle
Abstract
Since the isolation of graphene in 2004, the field of Van der Waals (or 2D) materials has grown to become a major focus of condensed matter physics. 2D crystals have been found with metallic, semi-conductor or superconductor properties, and more recently [1][2] with intrinsic magnetism. Among these newly found 2D magnets, CrSBr[3] stands out for being both an anti-ferromagnet and a semi-conductor, on top of being one of the few 2D magnets stable under ambient conditions.
Our team in Basel use NV center magnetometry [4][5] to image the magnetic properties of thin CrSBr flakes at the nanoscale. We realized that we could use the parts of a single flake with various thickness (2,3,4-layers etc.) to engineer magnetic textures in the flake. In particular we could create anti-ferromagnetic domains in CrSBr bilayer through a process that we call « lateral exchange bias ». This demonstrates the first observation of anti-ferromagnetic domains in a 2D magnet, an important step for both fundamental physics and potential applications in spintronics.
During my talk I will introduce the NV center magnetometer that we developed in Basel, as well as the concepts that allowed us to measure and control the antiferromagnetic order in the flakes.
[1] B. Huang et al. Nature 546, 270 (2017)[2] C. Gong et al. Nature 546, 265 (2017)
[3] K. Lee et al. Nano Lett. 21, 3511 (2021)
[4] L. Thiel et al. Science 364, 973 (2019)
[5] M. A. Tschudin et al. Nat. Commun. 15, 1 (2024)