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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
Bilayer orthogonal ferromagnetism in CrTe2-based van der Waals system
Chiara Bigi1, Cyriack Jego2, Vincent Polewczyk2,3
1Synchrotron SOLEIL, Saint-Aubin, France. chiara.bigi@synchrotron-soleil.fr.
Abstract:
Systems with pronounced spin anisotropy are pivotal in advancing magnetization switching and spin-wave generation mechanisms that are fundamental to spintronic technologies. Quasi-van der Waals ferromagnets like Cr1+δTe2 represent seminal materials in this field, renowned for their delicate balance between frustrated layered geometries and magnetism. Despite extensive investigation, the nature of their magnetic ground state and the mechanism of spin reorientation under external fields and varying temperatures remain contested. Here, we exploit complementary techniques to reveal a previously overlooked magnetic phase in Cr1+δTe2 (δ = 0.25 - 0.50), which we term orthogonal-ferromagnetism. This phase consists of atomically sharp single layers of in-plane and out-of-plane maximally canted ferromagnetic blocks, which differs from the stacking of multiple heterostructural elements required for crossed magnetism. Contrary to earlier reports of gradual spin reorientation in CrTe2-based systems, we present evidence for abrupt spin-flop-like transitions. This discovery further highlights Cr1+δTe2 compounds as promising candidates for spintronic and orbitronic applications, opening new pathways for device engineering.
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