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M. Nur Hasan

Publications and source records attributed to M. Nur Hasan.

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A Community-Developed Domain Ontology for Magnetic Materials

Magnetic materials play a crucial role in energy-related technologies, mobility, and sensing, but their complex multiscale behaviour and the coexistence of multiple unit systems pose persistent challenges for data exchange and interpretation. This paper presents a domain ontology for magnetic materials, developed within the European Union funded Magnetic Multiscale Modelling Suite (MaMMoS) project and aligned with the Elementary Multiperspective Material Ontology (EMMO). The ontology formalises intrinsic, hysteretic, and microstructural properties across multiple length scales and supports semantic interoperability between simulation tools, databases, and experimental workflows. One key feature of the ontology is its code-based and human-readable structure, enabled through the EMMOntoPy framework, which allows for direct manipulation and versioning without relying on opaque .owl or .ttl files. This facilitates collaborative development and improves transparency. The ontology supports FAIR (Findable, Accessible, Interoperable, Reusable) principles and is openly available for extension by the community. The aim of the MaMMoS project is to foster reproducibility, improve traceability, and promote the adoption of ontology in the magnetism domain. The ontology that has been developed already serves as the foundation for multiple software tools that handle all kinds of magnetic material data.

cond-mat.mtrl-sci

Observation of correlation-driven topological transport and robust ferromagnetism in 2D CrS$_2$

The realization of correlated layered magnets hosting robust ferromagnetism with emergent topological transport remains a key challenge in quantum materials. Here we report the first catalyst-free chemical vapour deposition growth of layered 1T-CrS$_2$, establishing a highly stable vdWs ferromagnet with an out-of-plane easy-axis anisotropy and a Curie temperature above room temperature. Transport measurements reveal a semimetal--insulator crossover near 80 K and pronounced negative magnetoresistance up to 350 K. A topological Hall effect emerges below 30 K, a rare signature of correlated transport in layered transition-metal dichalcogenide ferromagnets. First-principles calculations show that spin--orbit coupling gaps Dirac-like crossings, while electronic correlations reconstruct the Fermi surface by suppressing electron pockets and reducing the carrier density, enhancing momentum-dependent out-of-plane spin polarization. Magnetic measurements, supported by Heisenberg exchange calculations, reveal strong nearest-neighbour ferromagnetic exchange that stabilizes long-range ferromagnetism. Our results establish 1T-CrS$_2$ as a rare correlated 3$d$ layered ferromagnet in which electronic correlations and spin--orbit coupling cooperatively drive emergent topological transport.

cond-mat.mtrl-sci