161 citations · 292 across the 11 of their papers we have counts for
11 papers
Direct observation of locally modified excitonic effect within a moiré unit cell in twisted bilayer graphene
Ming Liu, Ryosuke Senga, Masanori Koshino +2
Bilayer graphene, forming moiré superlattices, possesses distinct electronic and optical properties derived from the hybridization of energy band and the emergence of van Hove sing…
Core-hole induced misalignment between Van-Hove singularities and K-edge fine structure in carbon nanotubes
Martin Unzog, Alexey Tal, Pedro Melo +4
We investigate the relationship between the K-edge fine structure of isolated single-wall carbon nanotubes (SWCNTs) and the Van Hove singularities (VHSs) in the conduction band den…
Direct observation of the vanishing EELS cross section in graphene
Alberto Guandalini, Ryosuke Senga, Yung-Chang Lin +5
In transmission electron energy-loss spectroscopy, the cross section in 2D is quenched by kinematic effects once the momentum transfer becomes smaller than a critical value set by…
Imaging of isotope diffusion using atomic-scale vibrational spectroscopy
Ryosuke Senga, Yung-Chang Lin, Shigeyuki Morishita +4
The spatial resolutions of even the most sensitive isotope analysis techniques based on light or ion probes are limited to a few hundred nanometres. Although vibration spectroscopy…
Excitonic effects in energy loss spectra of freestanding graphene
Alberto Guandalini, Ryosuke Senga, Yung-Chang Lin +8
In this work we perform electron energy-loss spectroscopy (EELS) of freestanding graphene with high energy and momentum resolution to disentangle the quasielastic scattering from t…
Deciphering the Intense Post-Gap Absorptions of Monolayer Transition Metal Dichalcogenides
Jinhua Hong, Masanori Koshino, Ryosuke Senga +3
Rich valleytronics and diverse defect-induced or interlayer pre-bandgap excitonics have been extensively studied in transition metal dichalcogenides (TMDCs), a system with fascinat…