We have used angle resolved photoemission spectroscopy to investigate the band structure of ReS2, a transition-metal dichalcogenide semiconductor with a distorted 1T crystal structure. We find a large number of narrow valence bands, which we attribute to the combined influence of the structural distortion and spin-orbit coupling. We further image how this leads to a strong in-plane anisotropy of the electronic structure, with quasi-one-dimensional bands reflecting predominant hopping along zig-zag Re chains. We find that this does not persist up to the top of the valence band, where a more three-dimensional character is recovered with the fundamental band gap located away from the Brillouin zone centre along kz. These experiments are in good agreement with our density-functional theory calculations, shedding new light on the bulk electronic structure of ReS2, and how it can be expected to evolve when thinned to a single layer.
@article{arxiv.1703.04725,
title = {Narrow-band anisotropic electronic structure of ReS$_2$},
author = {D. Biswas and A. M. Ganose and R. Yano and J. M. Riley and L. Bawden and O. J. Clark and J. Feng and L. Collins-Mcintyre and W. Meevasana and T. K. Kim and M. Hoesch and J. E. Rault and T. Sasagawa and D. O. Scanlon and P. D. C. King},
journal= {arXiv preprint arXiv:1703.04725},
year = {2017}
}