285 citations · 2.6k across the 51 of their papers we have counts for
21 papers · 1 filter
Carrier-density dependence of magnetotransport in correlated Dirac semimetal CaIrO
Rinsuke Yamada, Jun Fujioka, Minoru Kawamura +8
We report the carrier density dependence of the magnetotransport property in the correlated Dirac semimetal CaIrO. In the dilute carrier density region ( $\sim 2.2 \…
Unraveling a chemical-bond-driven root of topology in three-dimensional chiral crystals
Shungo Aoyagi, Shunsuke Kitou, Yuiga Nakamura +6
Chirality manifests across multiple scales, yielding unique phenomena that break mirror symmetry. In chiral materials, unexpectedly large spin-filtering or photogalvanic effects ha…
Designing single and degenerate flat bands in the kagome lattice with long-range hopping
Yuta Taguchi, Motoaki Hirayama, Takashi Miyake
We investigate the electronic structure of the kagome lattice model with first, second, and two kinds of third nearest-neighbor hoppings. We reveal that by tuning the third nearest…
Spontaneous topological Hall effect induced by non-coplanar antiferromagnetic order in intercalated van der Waals materials
H. Takagi, R. Takagi, S. Minami +14
In ferromagnets, electric current generally induces transverse Hall voltage in proportion to magnetization (anomalous Hall effect), and it is frequently used for electrical readout…
Signature of topological band crossing in ferromagnetic Cr1/3NbSe2 epitaxial thin film
Bruno Kenichi Saika, Satoshi Hamao, Yuki Majima +14
In intercalated transition metal dichalcogenides (I-TMDC), transition metal intercalation introduces magnetic phases which in some cases induce topological band crossing. However,…
Efficient hydrogen evolution reaction due to topological polarization
Ming-Chun Jiang, Guang-Yu Guo, Motoaki Hirayama +3
Materials carrying topological surface states (TSS) provide a fascinating platform for the hydrogen evolution reaction (HER). Based on systematic first-principles calculations for…
Interstitial-Electron-Induced Topological Molecular Crystals
Tonghua Yu, Ryotaro Arita, Motoaki Hirayama
Topological phases usually are unreachable in molecular solids, which are characteristic of weakly dispersed energy bands with a large gap, in contrast to topological materials. In…
Quantum transport observed in films of magnetic topological semimetal EuSb
Mizuki Ohno, Masaki Uchida, Ryosuke Kurihara +10
We report fabrication of EuSb single-crystalline films and investigation of their quantum transport. First-principles calculations demonstrate that EuSb is a magnetic topol…
Multipole representation for anisotropic Coulomb interactions
Shoma Iimura, Motoaki Hirayama, Shintaro Hoshino
Multipole representation is proposed for the anisotropic Coulomb interactions in solids. Any local interactions can be expressed as the product of two multipole operators, and the…
First-Principles Design of Halide-Reduced Electrides: Magnetism and Topological Phases
Tonghua Yu, Motoaki Hirayama, José A. Flores-Livas +3
We propose a design scheme for potential electrides derived from conventional materials. Starting with rare-earth-based ternary halides, we exclude halogens and perform global stru…
Enhancement of transverse thermoelectric conductivity originating from stationary points in nodal line
Susumu Minami, Fumiyuki Ishii, Motoaki Hirayama +3
Motivated by the recent discovery of a large anomalous Nernst effect in CoMnGa, Fe (=Al, Ga) and CoSnS, we performed a first-principles study to clarify the…
Anomalous dielectric response in insulators with the pi Zak phase
Yusuke Aihara, Motoaki Hirayama, Shuichi Murakami
In various topological phases, nontrivial states appear at the boundaries of the system. In this paper, we investigate anomalous dielectric response caused by such states caused by…
Higher-Order Topological Crystalline Insulating Phase and Quantized Hinge Charge in Topological Electride Apatite
Motoaki Hirayama, Ryo Takahashi, Satoru Matsuishi +2
In higher-order topological insulators, bulk and surface electronic states are gapped, while there appear gapless hinge states protected by spatial symmetry. Here we show by ab ini…
Material design with the van der Waals stacking of bismuth-halide chains realizing a higher-order topological insulator
Ryo Noguchi, Masaru Kobayashi, Zhanzhi Jiang +28
The van der Waals (vdW) materials with low dimensions have been extensively studied as a platform to generate exotic quantum properties. Advancing this view, a great deal of attent…
Pressure-induced topological phase transition in noncentrosymmetric elemental Tellurium
Toshiya Ideue, Motoaki Hirayama, Hiroaki Taiko +6
Recent progress in understanding the electronic band topology and emergent topological properties encourage us to reconsider the band structure of well-known materials including el…
Radial spin texture in elemental tellurium with chiral crystal structure
M. Sakano, M. Hirayama, T. Takahashi +18
The chiral crystal is characterized by a lack of mirror symmetry and an inversion center, resulting in the inequivalent right- and left-handed structures. In the noncentrosymmetric…
Electrides as a New Platform of Topological Materials
Motoaki Hirayama, Satoru Matsuishi, Hideo Hosono +1
Recent discoveries of topological phases realized in electronic states in solids have revealed an important role of topology, which ubiquitously appears in various materials in nat…
Topological semimetals studied by ab initio calculations
Motoaki Hirayama, Ryo Okugawa, Shuichi Murakami
In topological semimetals such as Weyl, Dirac, and nodal-line semimetals, the band gap closes at points or along lines in k space which are not necessarily located at high-symmetry…
Spinless hourglass nodal-line semimetals
Ryo Takahashi, Motoaki Hirayama, Shuichi Murakami
Nodal-line semimetals, one of the topological semimetals, have degeneracy along nodal lines where the band gap is closed. In many cases, the nodal lines appear accidentally, and in…
Topological Dirac Nodal Lines and Surface Charges in fcc Alkaline Earth Metals
Motoaki Hirayama, Ryo Okugawa, Takashi Miyake +1
In nodal-line semimetals, the gaps close along loops in space, which are not at high-symmetry points. Typical mechanisms for the emergence of nodal lines involve mirror s…
Weyl Node and Spin Texture in Trigonal Tellurium and Selenium
Motoaki Hirayama, Ryo Okugawa, Shoji Ishibashi +2
We study Weyl nodes in materials with broken inversion symmetry. We find based on first-principles calculations that trigonal Te and Se have multiple Weyl nodes near the Fermi leve…