Electromechanical properties of graphene drumheads.
We determined the electromechanical properties of a suspended graphene layer by scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS) measurements, as well as computational simulations of the graphene-membrane mechanics and morphology. A graphene membrane was continuously deformed by controlling the competing interactions with a STM probe tip and the electric field from a back-gate electrode. The probe tip-induced deformation created a localized strain field in the graphene lattice. STS measurements on the deformed suspended graphene display an electronic spectrum completely different from that of graphene supported by a substrate. The spectrum indicates the formation of a spatially confined quantum dot, in agreement with recent predictions of confinement by strain-induced pseudomagnetic fields.
Center for Nanoscale Science and Technology, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA.
Nikolai N
NN
Klimov
Suyong
S
Jung
Shuze
S
Zhu
Teng
T
Li
C Alan
CA
Wright
Santiago D
SD
Solares
David B
DB
Newell
Nikolai B
NB
Zhitenev
Joseph A
JA
Stroscio