Abstract:
Research on single layers and few layers of materials has demonstrated abundant cases of novel properties, including lattice and charge distortions, magnetic ordering, topological electronic transitions, superconductivity, etc., that are drastically different from the corresponding bulk cases. Transition metal dichalcogenides (TMDCs), which form a huge group of van der Waals layered systems, are excellent parent materials for the study in reduced dimension. In this talk, I will briefly introduce the principle of the major tool, angle-resolved photoemission spectroscopy (ARPES), used in my research and present my recent works on few-layer TMDCs and their heterostructures, specifically, for semiconductor-to-semimetal transition in PtTe2, substrate mediated charge instability in TiTe2 single layer, and coherent coupling in TiTe2/TiSe2 Moiré bilayer.