Layered Antiferromagnetism Induces Large Negative Magnetoresistance in the van der Waals Semiconductor CrSBr. Issue 37 (9th August 2020) - Telford, Evan J.
Abstract: The recent discovery of magnetism within the family of exfoliatable van der Waals (vdW) compounds has attracted considerable interest in these materials for both fundamental research and technological applications. However, current vdW magnets are limited by their extreme sensitivity to air, low ordering temperatures, and poor charge transport properties. Here the magnetic and electronic properties of CrSBr are reported, an air‐stable vdW antiferromagnetic semiconductor that readily cleaves perpendicular to the stacking axis. Below its Néel temperature, T N = 132 ± 1 K, CrSBr adopts an A‐type antiferromagnetic structure with each individual layer ferromagnetically ordered internally and the layers coupled antiferromagnetically along the stacking direction. Scanning tunneling spectroscopy and photoluminescence (PL) reveal that the electronic gap is ΔE = 1.5 ± 0.2 eV with a corresponding PL peak centered at 1.25 ± 0.07 eV. Using magnetotransport measurements, strong coupling between magnetic order and transport properties in CrSBr is demonstrated, leading to a large negative magnetoresistance response that is unique among vdW materials. These findings establish CrSBr as a promising material platform for increasing the applicability of vdW magnets to the field of spin‐based electronics. Abstract : CrSBr is an air‐stable, intrinsically magnetic, van der Waals semiconductor with an electronic bandgap ∆E = 1.5 ± 0.2 eV and photoluminescence peak centered at 1.25 ± 0.07 eV. Magnetometry and magnetotransport measurements demonstrate that CrSBr exhibits intraplanar ferromagnetic ordering and interplanar antiferromagnetic ordering below T N ≈ 132 ± 1 K, producing a large intrinsic negative magnetoresistance.