报告时间：2025年11月13日 16:00

报告地点：物理楼W101

内容摘要：Control over materials thickness down to the single-atom scale has emerged as a powerful tuning parameter for manipulating not only the single-particle band structures of solids, but increasingly also their interacting electronic states and phases. A particularly attractive materials system in which to explore this is the transition-metal dichalcogenides (TMDs), both because of their naturally-layered van der Waals structures and the wide variety of materials properties which they are known to host. Yet, how the intricate correlated electron states that underpin many of these materials’ properties evolve when the compound is thinned to the single-layer limit remains – in many cases – a controversial question. Here, I will discuss our work attempting to address this by integrating monolayer materials growth by molecular-beam epitaxy with electronic structure studies via in situ angle-resolved photoemission (ARPES) and ARPES-based microscopy. I will introduce a new method for achieving enhanced nucleation in monolayer TMD growth, which leads to a step-change in the quality and uniformity of our fabricated samples. I will discuss the electronic structures that we can observe from van der Waals heterostructures fabricated in this way, considering, in particular, the role of environmental screening and interfacial coupling. I will focus on two prototypical charge-density wave materials, NbSe₂ and TiSe₂, addressing controversies surrounding the origins and evolution of their collective states and uncovering new routes to stabilise emergent long-wavelength super-periodicities.

报告人简介：Phil King is Professor of Physics and Director of Research in the School of Physics and Astronomy at the University of St Andrews, UK. He obtained his PhD in surface physics from the University of Warwick in 2009, following which he undertook postdoctoral research at St Andrews and as a Kavli postdoctoral fellow at Cornell University, before returning to a faculty position in St Andrews in 2013. There, he leads a group focused on investigating the electronic structure of quantum materials, and in tuning this via thin-film materials synthesis.