Title: Fragile magnetism in metallic transition metal chalcogenides
Abstract: Magnetism in layered van der Waals (vdW) materials provides a remarkable setting to revisit long-standing concepts in solid-state physics and to explore new pathways for device applications. Unlike conventional magnetic thin films, vdW magnets display extraordinary sensitivity to small changes in composition, stacking, and dimensionality, which can dramatically alter their ground states. In this talk, I will highlight how subtle modifications - such as minute stoichiometric changes or magnetic alloying inside the vdW skeleton - can switch magnetism, stabilize unexpected high-temperature order, or reshape the low-energy flat electronic bands. I will also discuss the role of interlayer interactions as a powerful control knob, underscoring how the fragile magnetism here reflects the broader theme of tunability in vdW quantum materials. Finally, I’ll show our recent effort of integrating kGauss level magnetic field with ARPES, paving way for future in situ spectral investigations of metallic magnets.