107 citations · 386 across the 22 of their papers we have counts for
22 papers
Magnetic-field periodic quantum Sondheimer oscillations in thin-film graphite
Toshihiro Taen, Andhika Kiswandhi, Toshihito Osada
Materials with the mesoscopic scales have provided an excellent platform for quantum-mechanical studies. Among them, the periodic oscillations of the electrical resistivity against…
Quantized thermoelectric Hall plateau in the quantum limit of graphite as a nodal line semimetal
Andhika Kiswandhi, Tomotaka Ochi, Toshihiro Taen +3
We performed thermoelectric Hall conductivity measurements on single-crystal graphite in the quantum limit up to 13 T. Both electrical and thermoelectric transport measure…
Weak localization on moiré superlattice in twisted double bilayer graphene
Masaki Kashiwagi, Toshihiro Taen, Kazuhito Uchida +3
Moiré superlattice created by twist stacking has multiple physical properties. These physical properties depend on the twist angle, hence investigation of the twist angle dependenc…
Thermoelectric Hall Effect at High-Magnetic-Field Quantum Limit in Graphite as a Nodal-Line Semimetal
Toshihito Osada, Tomotaka Ochi, Toshihiro Taen
The high-magnetic-field thermoelectric effect in nodal-line semimetals with straight nodal lines was investigated. Three-dimensional (3D) Dirac/Weyl semimetals exhibit constant the…
Thermoelectric Effect at Quantum Limit in Two-Dimensional Organic Dirac Fermion System with Zeeman Splitting
Toshihito Osada
The thermoelectric effect in a two-dimensional (2D) massless Dirac fermion (DF) system at the quantum limit is discussed to verify the prediction of high-performance thermopower in…
Possible Nonlinear Anomalous Thermoelectric Effect in Organic Massive Dirac Fermion System
Toshihito Osada, Andhika Kiswandhi
We propose a novel current-induced thermoelectric phenomenon, the nonlinear anomalous Ettingshausen effect (AEE), at zero magnetic field in inversion-asymmetric conductors. As an e…
Observation of Possible Nonlinear Anomalous Hall Effect in Organic Two-Dimensional Dirac Fermion System
Andhika Kiswandhi, Toshihito Osada
We report the observation of nonlinear anomalous Hall effect (NLAHE) in the multilayered organic conductor -(BEDT-TTF)I in the charge order (CO) insulating phase just un…
Experimental Confirmation of Massive Dirac Fermions in Weak Charge-Ordering State in α-(BEDT-TTF)_2I_3
Kenta Yoshimura, Mitsuyuki Sato, Toshihito Osada
The electronic structure of weak charge-ordering (CO) state just below the critical pressure in an organic conductor α-(BEDT-TTF)_2I_3 was experimentally investigated using peak st…
Possible Current-Induced Phenomena and Domain Control in an Organic Dirac Fermion System with Weak Charge Ordering
Toshihito Osada, Andhika Kiswandhi
We show that when the electron and hole densities are unbalanced, observable nonlinear anomalous Hall effect and current-induced orbital magnetization appear at zero magnetic field…
Experimental Confirmation of Quantum Hall Ferromagnetic State in an Organic Dirac Fermion System
Mitsuyuki Sato, Takako Konoike, Toshihito Osada
We have experimentally confirmed the quantum Hall ferromagnetic state with Chern number ν=0, characterized by the helical edge state, in a layered organic Dirac fermion system α-(B…
Topological Properties of τ-Type Organic Conductors with a Checkerboard Lattice
Toshihito Osada
Although the topological phases are difficult to be realized in organic molecular crystals, we demonstrate here that they can emerge in the τ-type organic layered conductors, τ-(ED…
Highly anisotropic interlayer magnetoresistance in ZrSiS nodal-line Dirac semimetal
M. Novak, S. N. Zhang, F. Orbanic +11
We instigate the angle-dependent magnetoresistance (AMR) of the layered nodal-line Dirac semimetal ZrSiS for the in-plane and out-of-plane current directions. This material has rec…
Anisotropy of Dirac cones and van Hove singularity in an organic Dirac fermion system
Ayaka Mori, Mitsuyuki Sato, Takeshi Yajima +3
We propose an experimental method to examine the in-plane anisotropy of electronic structure in layered conductors. In the method, we measure the interlayer magnetoresistance as a…
Double carrier transport in electron doped region in black phosphorus FET
Kohei Hirose, Toshihito Osada, Kazuhito Uchida +4
The double carrier transport has been observed in thin film black phosphorus (BP) field effect transistor (FET) devices in highly electron doped region. BP thin films with typical…
Topological Insulator State due to Finite Spin-Orbit Interaction in an Organic Dirac Fermion System
Toshihito Osada
Recently, Valenti et al. pointed out the significance of the spin-orbit interaction (SOI) in organic materials, and explained the anomalous insulating behavior of a Dirac semimetal…
Thickness-dependent phase transition in graphite under high magnetic field
Toshihiro Taen, Kazuhito Uchida, Toshihito Osada
Various electronic phases emerge when applying high magnetic fields in graphite. However, the origin of a semimetal-insulator transition at is still not…
Electronic Structure and the Properties of Phosphorene Systems
Shuhei Fukuoka, Toshihiro Taen, Toshihito Osada
A single atomic layer of black phosphorus, phosphorene, was experimentally realized in 2014. It has a puckered honeycomb lattice structure and a semiconducting electronic structure…
Surface Transport in the ν=0 Quantum Hall Ferromagnetic State in the Organic Dirac Fermion System
Toshihito Osada
We discuss the surface magnetotransport in the quantum Hall (QH) ferromagnetic state expected in the organic Dirac fermion system α-(BEDT-TTF)_2I_3. The QH ferromagnetic state is o…
Edge State and Intrinsic Hole Doping in Bilayer Phosphorene
Toshihito Osada
Using a simple LCAO model by Harrison, we have qualitatively studied the edge state of bilayer phosphorene, which is a unit structure of the layered crystal of black phosphorus. Th…
Phase Diagram for the Hofstadter butterfly and integer quantum Hall effect in three dimensions
M. Koshino, H. Aoki, T. Osada +2
We give a perspective on the Hofstadter butterfly (fractal energy spectrum in magnetic fields), which we have shown to arise specifically in three-dimensional(3D) systems in our pr…
Field-Induced SDW and Butterfly Spectrum in Three Dimensions
M. Koshino, H. Aoki, T. Osada
Landau's quantization for incompletely nested Fermi surfaces is known to give rise to magnetic-field-induced spin-density waves(FISDW) in two-dimensional organic metals. Here we sh…
Hofstadter butterfly and integer quantum Hall effect in three dimensions
M. Koshino, H. Aoki, K. Kuroki +2
For a three-dimensional lattice in magnetic fields we have shown that the hopping along the third direction, which normally tends to smear out the Landau quantization gaps, can rat…