Determination of the band parameters of bulk 2H-MX2(M = Mo, W; X = S, Se) by angle-resolved photoemission spectroscopy.
Monolayer MX2(M = Mo, W; X = S, Se) has recently been drawn much attention due to their application possibility as well as the novel valley physics. On the other hand, it is also important to understand the electronic structures of bulk MX2for material applications since it is very challenging to grow large size uniform and sustainable monolayer MX2. We performed angle-resolved photoemission spectroscopy and tight binding calculations to investigate the electronic structures of bulk 2H-MX2. We could extract all the important electronic band parameters for bulk 2H-MX2, including the band gap, direct band gap size at K (-K) point and spin splitting size. Upon comparing the parameters for bulk 2H-MX2(our work) with mono- and multi-layer MX2(published), we found that stacked layers, substrates for thin films, and carrier concentration significantly affect the parameters, especially the band gap size. The origin of such effect is discussed in terms of the screening effect.
Center for Correlated Electron Systems, Institute for Basic Science, Seoul, 08826, Korea.|Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Korea.|Department of Physics, Incheon National University, Incheon, 22012, Korea.
Beom Seo
BS
Kim
Max-Planck-Institut für Physik komplexer System, 01187, Dresden, Germany.
Jun-Won
JW
Rhim
Department of Physics, Pohang University of Science and Technology, Pohang, 37673, Korea.|Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
Beomyoung
B
Kim
Center for Correlated Electron Systems, Institute for Basic Science, Seoul, 08826, Korea.|Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Korea.
Changyoung
C
Kim
Department of Physics, Incheon National University, Incheon, 22012, Korea.
Seung Ryong
SR
Park