Controlling of the Dirac band states of Pb-deposited graphene by using work function difference
Abstract
We have performed scanning tunneling microscopy (STM) and angle-resolved photoemission spectroscopy (ARPES) in Pb-deposited bilayer graphene (BLG) on the SiC(0001) substrate to investigate the dependence of the electronic structures on the Pb-deposition amount. We have observed that the Pb atoms form islands by STM and the π bands of the BLG shift toward the Fermi level by ARPES. This hole-doping-like energy shift is enhanced as the amount of Pb is increased, and we were able to tune the Dirac gap to the Fermi level by 4 ML deposition. Considering the band dispersion, we suggest that the hole-doping-like effect is related to the difference between the work functions of Pb islands and BLG/SiC; the work function of BLG/SiC is lower than that of Pb. Our results propose an easy way of band tuning for graphene with an appropriate selection of both the substrate and deposited material.
- Publication:
-
AIP Advances
- Pub Date:
- August 2020
- DOI:
- 10.1063/5.0013797
- arXiv:
- arXiv:2005.06770
- Bibcode:
- 2020AIPA...10h5314T
- Keywords:
-
- Condensed Matter - Materials Science;
- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- AIP Advances 10, 085314 (2020)