Research Projects

Layered magnetic Weyl semimetals have emerged as a new class in topological quantum materials, combining rich topological physics with exotic magnetic and transport phenomena. Among the most compelling features are the giant anomalous Hall effect (AHE) and topological Hall effect (THE) that are signatures of intrinsic Berry curvature and skyrmions. These extraordinary Hall responses arise from complex interplay between Berry curvature hotspots, non-coplanar spin textures (magnetic skyrmions), and topological band structures, but we lack the crystal engineering strategies to optimize these effects simultaneously. This project proposes a systematic engineering approach and growth of high-quality single crystals of AV₃Sb₅ (A= Rb, K, Cs) and Ln₃Sn₇ (Ln = rare earths) via advanced flux methods. By strategical chemical substitutions at A, V, or Ln sites, we aim to tune the chemical potential at the maximal of Berry curvature, adjust spin–orbit coupling strength, manipulate band splittings, and induce disorder band broadening. This approach has the potential to maximize the anomalous Hall effects. Additionally, we will substitute dopants to modulate exchange interactions, anisotropy energy and non-coplaner spin orders that results in complex spin configurations such as skyrmions that generates topological Hall responses. By this material engineering, we expect to identify configurations that optimize both anomalous and topological Hall effects. Magnetic characterization and AC susceptibility measurements will help us to probe how the spin structures evolve within the crystal. Magnetotransport and Hall measurements combined with advanced analysis methods such as two band model fitting and TYJ scaling-will enable us to disentangle ordinary, anomalous, and topological Hall contributions. This approach allows us to pinpoint the dominant scattering mechanisms at play and to fine-tune them maximum. DFT modeling will help to identify Berry curvature hotspots-the regions that drive maximal Hall responses. Ultimately it will reveal how intricate spin texture related topological Hall effects, intrinsic Berry curvature mechanisms, and band structure topologies manifest in observable giant Hall signals. This knowledge will serve as a pathway to engineer new materials with record breaking anomalous and topological Hall effects for next generation high-efficiency spintronic and Hall sensing devices.