RT Journal Article
SR Electronic
T1 Giant gate-tunable bandgap renormalization and excitonic effects in a 2D semiconductor
JF Science Advances
JO Sci Adv
FD American Association for the Advancement of Science
SP eaaw2347
DO 10.1126/sciadv.aaw2347
VO 5
IS 7
A1 Qiu, Zhizhan
A1 Trushin, Maxim
A1 Fang, Hanyan
A1 Verzhbitskiy, Ivan
A1 Gao, Shiyuan
A1 Laksono, Evan
A1 Yang, Ming
A1 Lyu, Pin
A1 Li, Jing
A1 Su, Jie
A1 Telychko, Mykola
A1 Watanabe, Kenji
A1 Taniguchi, Takashi
A1 Wu, Jishan
A1 Neto, A. H. Castro
A1 Yang, Li
A1 Eda, Goki
A1 Adam, Shaffique
A1 Lu, Jiong
YR 2019
UL http://advances.sciencemag.org/content/5/7/eaaw2347.abstract
AB Understanding the remarkable excitonic effects and controlling the exciton binding energies in two-dimensional (2D) semiconductors are crucial in unlocking their full potential for use in future photonic and optoelectronic devices. Here, we demonstrate large excitonic effects and gate-tunable exciton binding energies in single-layer rhenium diselenide (ReSe2) on a back-gated graphene device. We used scanning tunneling spectroscopy and differential reflectance spectroscopy to measure the quasiparticle electronic and optical bandgap of single-layer ReSe2, respectively, yielding a large exciton binding energy of 520 meV. Further, we achieved continuous tuning of the electronic bandgap and exciton binding energy of monolayer ReSe2 by hundreds of milli–electron volts through electrostatic gating, attributed to tunable Coulomb interactions arising from the gate-controlled free carriers in graphene. Our findings open a new avenue for controlling the bandgap renormalization and exciton binding energies in 2D semiconductors for a wide range of technological applications.