1.8k citations · 14.7k across the 129 of their papers we have counts for
131 papers
Up/down-conversion of infrared light by few-layer graphene polytypes
Patrick Johansen Sarsfield, Takaaki V. Joya, Takuto Kawakami +2
Optical nonlinearity of materials with broken inversion symmetry enables two-photon processes where an incoming pair of photons can generate an up-converted photon with the combine…
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…
Twist-configured moire-moire reconstruction governs diverse commensurate double-moire phases in twisted bilayer graphene on h-BN
Yuta Seo, Naoto Nakatsuji, Jimpei Kawase +6
The coexistence of multiple moire lattices in van der Waals heterostructures raises a fundamental question: how do distinct moire patterns interact and reconstruct? Here, we invest…
Landau levels and magneto-optics in 30 quasi-periodic twisted bilayer graphene
Masaru Hitomi, Takuto Kawakami, Mikito Koshino
We develop a theoretical framework for Landau levels in quasi-periodic twisted bilayer graphene at a twist angle, a system without translational symmetry but possessing…
One-Dimensional Electronic States in a Moiré Superlattice of Twisted Bilayer WTe2
Takuto Kawakami, Hayato Tateish, Daiki Yoshida +10
One-dimensional (1D) moiré superlattices provide a new route to engineering reduced-dimensional electronic states in van der Waals materials, yet their electronic structure and mic…
Ferroelectricity in a magnon Bose-Einstein condensate: Nonreciprocal superfluidity, exceptional points, and Majorana bosons
Kazuki Yamamoto, Takuto Kawakami, Mikito Koshino
We investigate a ferroelectric instability of a magnon Bose-Einstein condensate, mediated by its interaction with an electric field through a geometric Aharonov-Casher (AC) phase.…