3 papers
cond-mat.mes-hall2026
Second-harmonic generation in twisted double bilayer graphene: Double-resonant enhancement from moiré flat bands
Takaaki V. Joya, Takuto Kawakami, Mikito Koshino
We theoretically investigate second-harmonic generation (SHG) in twisted double bilayer graphene (TDBG) with AB--AB and AB--BA stacking configurations using a perturbative approach…
cond-mat.mes-hall2026
Resonant Structure of Second Harmonic Generation in Multilayer Graphene Polytypes
Patrick Johansen Sarsfield, Takaaki V. Joya, Takuto Kawakami +2
Second harmonic generation (SHG) is a powerful optical tool for identifying non-centrosymmetric crystalline structures. Here, we analyze SHG in multilayer graphenes (MLG), with a f…
cond-mat.mes-hall2025
Shift current response in twisted double bilayer graphenes
Takaaki V. Joya, Takuto Kawakami, Mikito Koshino
We calculate the shift current response in twisted double bilayer graphenes (TDBG) by applying the perturbative approach to the effective continuum Hamiltonian. We have performed a…