Pt-doped WS2 the first Extrinsic Dilute Magnetic 2D Semiconductor

Ya-Ping Hsieh^1*

¹1Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan

* Presenter:Ya-Ping Hsieh, email:yphsieh@gate.sinica.edu.tw

Two-dimensional (2D) magnets have emerged as a promising platform for both fundamental studies of low-dimensional magnetism and the development of next-generation spintronic devices. However, intrinsic 2D magnetic materials often suffer from low Curie temperatures, environmental instability, and limited tunability, posing significant challenges for practical device integration. To overcome these limitations, extrinsic dilute magnetic semiconductors (DMS) provide an alternative route to achieving robust magnetism in 2D systems. In extrinsic DMS, a non-magnetic dopant interacts with a semiconducting host, inducing magnetic functionality without the need for intrinsic magnetic elements. This approach allows for precise control over atomic-scale interactions making them ideal platforms for investigating magnetic phenomena in 2D materials. Here, we present the first realization of an extrinsic 2D DMS in platinum-doped tungsten disulfide (Pt-WS₂). Using a bottom-up synthesis approach, we achieve a uniform and highly crystalline monolayer, where platinum selectively occupies the tungsten sub-lattice. The orbital hybridization between W 4d and Pt 5d orbitals leads to spin-selective states, resulting in a pronounced valley-Zeeman splitting. Our combined experimental and theoretical investigations reveal a sizable ferromagnetic response with a Curie temperature of approximately 375 K. These findings demonstrate a novel strategy for engineering 2D magnetism through atomic-level interaction design, paving the way for future advancements in spintronic devices, valleytronic applications, and magnetic nanoactuation.

Keywords: 2D materials, ferromagnetic, tungsten sulfide(WS2), dilute magnetic semiconductors (DMS)