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O: Fachverband Oberflächenphysik
O 84: Electronic Structure of Surfaces I: Spectroscopy, Surface States
O 84.7: Talk
Thursday, March 21, 2024, 12:00–12:15, MA 144
Novel electronic structures from anomalous stackings in transition metal dichalcogenides — •Mihir Date1,2, Alex Louat1, Niels Schroeter2, and Matthew D. Watson1 — 1Diamond Light Source, Diamond Light Source, Harwell Science and Innovation Campus, Didcot, United Kingdom — 2Max Planck Institute of Microstructure Physics, Halle (Saale), Germany
Advances in photoemission spectroscopy, especially in terms of spatial resolution, have opened a plethora of possibilities in probing variations in the local electronic structure, which are elusive in traditional angle -resolved photoemission spectroscopy (ARPES) experiments. In our experiments, we have shown that in some "2H"-bulk transition metal dichalcogenides (TMDCs), MoS2, NbS2 and TaS2, minority regions on the sample show spectral signatures of quantum well states. Furthermore, we observe subtle differences in the spectral weight and band splitting in the hole-like pockets around M- and K-points in anomalously stacked MoS2, compared to the bandstructures of its 2H- and 3R-phases. We speculate such electronic structures are derived from local lattice imperfections, where the periodicity of the 2H stacking is broken along the c-axis. We propose that these stacking faults offer a convenient plane for sample cleaving and therefore, are easily captured in a surface sensitive technique like ARPES. Our work not only presents novel electronic structures of traditional TMDCs, but also highlights the strength and importance of spatially resolved ARPES measurements.
Keywords: Spatially resolved ARPES; Electronic structure; Anomalous stacking; TMDCs