학술논문
Strain-tunable Berry curvature in quasi-two-dimensional chromium telluride.
Document Type
article
Author
Chi, Hang; Ou, Yunbo; Eldred, Tim; Gao, Wenpei; Kwon, Sohee; Murray, Joseph; Dreyer, Michael; Butera, Robert; Foucher, Alexandre; Ambaye, Haile; Keum, Jong; Greenberg, Alice; Liu, Yuhang; Neupane, Mahesh; de Coster, George; Vail, Owen; Taylor, Patrick; Folkes, Patrick; Rong, Charles; Yin, Gen; Lake, Roger; Ross, Frances; Lauter, Valeria; Heiman, Don; Moodera, Jagadeesh
Source
Nature Communications. 14(1)
Subject
Language
Abstract
Magnetic transition metal chalcogenides form an emerging platform for exploring spin-orbit driven Berry phase phenomena owing to the nontrivial interplay between topology and magnetism. Here we show that the anomalous Hall effect in pristine Cr2Te3 thin films manifests a unique temperature-dependent sign reversal at nonzero magnetization, resulting from the momentum-space Berry curvature as established by first-principles simulations. The sign change is strain tunable, enabled by the sharp and well-defined substrate/film interface in the quasi-two-dimensional Cr2Te3 epitaxial films, revealed by scanning transmission electron microscopy and depth-sensitive polarized neutron reflectometry. This Berry phase effect further introduces hump-shaped Hall peaks in pristine Cr2Te3 near the coercive field during the magnetization switching process, owing to the presence of strain-modulated magnetic layers/domains. The versatile interface tunability of Berry curvature in Cr2Te3 thin films offers new opportunities for topological electronics.