194 citations · 1.5k across the 46 of their papers we have counts for
47 papers
Disorder-Mediated Magnetism in Transition-Metal Dichalcogenide Monolayers: XS and XSe (X = Ti, V, Co, Mo, and Ru)
Chi-Cheng Lee, Yukiko Yamada-Takamura, Taisuke Ozaki
Magnetism in transition-metal dichalcogenide monolayers has attracted considerable attention, yet its nature remains elusive, particularly in monolayer 1T-VSe. Our first-princi…
Linear and nonlinear optical responses in the chiral multifold semimetal BeAu: A quantum-geometric perspective
Babu Baijnath Prasad, Taisuke Ozaki
Chiral topological semimetals provide a natural platform for exploring how multifold band topology and quantum geometry manifest in optical and photovoltaic responses. BeAu is a ch…
Closest Wannier functions to a given set of localized orbitals
Taisuke Ozaki
A non-iterative method is presented to calculate the closest Wannier functions (CWFs) to a given set of localized guiding functions, such as atomic orbitals, hybrid atomic orbitals…
Electronic band structure change with structural transition of buckled AuX monolayers induced by strain
Masahiro Fukuda, Taisuke Ozaki
This study investigates the strain-induced structural transitions of and the changes in electronic band structures of AuX (X=S, Se, Te, Si, Ge) and AuS…
Atomically-thin metallic Si and Ge allotropes with high Fermi velocities
Chin-En Hsu, Yung-Ting Lee, Chieh-Chun Wang +4
Silicon and germanium are the well-known materials used to manufacture electronic devices for the integrated circuits but they themselves are not considered as promising options fo…
Prediction of quaternary hydrides based on densest ternary sphere packings
Ryotaro Koshoji, Masahiro Fukuda, Taisuke Ozaki
We exhaustively search quaternary metal hydrides based on the (13-2-1) and (13-3-1) structures that are the two of the putative densest ternary sphere packings in cubic systems [R.…
Diverse densest ternary sphere packings
Ryotaro Koshoji, Taisuke Ozaki
The exploration of the densest sphere packings is a fundamental problem in mathematics and a wide variety of sciences including materials science. We present our exhaustive computa…
Densest ternary sphere packings
Ryotaro Koshoji, Taisuke Ozaki
We present our exhaustive exploration of the densest ternary sphere packings (DTSPs) for 45 radius ratios and 237 kinds of compositions, which is a packing problem of three kinds o…
The hidden competing phase revealed by first-principles calculations of phonon instability in the nearly optimally doped cuprate LaSrCuO
Chi-Cheng Lee, Ji-Yao Chiu, Yukiko Yamada-Takamura +1
The representative cuprate, LaMCuO, with M = Sr and is studied via first-principles calculations in the high-temperature tetragonal (HTT), low-temperature…
Methods for constructing parameter-dependent flat band lattices
Toshitaka Ogata, Mitsuaki Kawamura, Taisuke Ozaki
We present two methods for constructing a flat band (FB) system having a flat energy dispersion over the entire Brillouin zone within tight-binding model, where the resulting Hamil…
Scaling law for the Rashba-type spin splitting in quantum well films
Ryo Noguchi, Kenta Kuroda, Mitsuaki Kawamura +7
We use laser-based spin- and angle-resolved photoemission spectroscopy (laser-SARPES) with high-resolution, and experimentally determine, for the first time, the Rashba-parameters…
Densest binary sphere packings and phase diagram : revisited
Ryotaro Koshoji, Mitsuaki Kawamura, Masahiro Fukuda +1
We revisit the densest binary sphere packings (DBSP) under the periodic boundary conditions and present an updated phase diagram, including newly found 12 putative densest structur…
First-principles study on the stability and electronic structure of monolayer GaSe with trigonal-antiprismatic structure
Hirokazu Nitta, Takahiro Yonezawa, Antoine Fleurence +2
The structural stability and electronic states of GaSe monolayer with trigonal-antiprismatic (AP) structure, which is a recently discovered new polymorph, were studied by first-pri…
Unfolding optical transition weights of impurity materials for first-principles LCAO electronic structure calculations
Yung-Ting Lee, Chi-Cheng Lee, Masahiro Fukuda +1
A method to analyze optical transitions is developed by combining the Kubo-Greenwood formula with the unfolding method to construct an unfolded electronic band structure with optic…
Single-site orthogonalization for first-principles computations of exchange coupling constants
Asako Terasawa, Sonju Kou, Taisuke Ozaki +1
For accurate first-principles computations of exchange coupling constants by the Liechtenstein method with localized basis sets, we developed a scheme using the single-sit…
Electronic structure of a 3x3-ordered silicon layer on Al(111)
Y. Sato, Y. Fukaya, M. Cameau +11
Electronic structure of the 3x3 ordered-phase of a silicon (Si) layer on Al(111) has been studied by angle resolved photoemission spectroscopy (ARPES) technique using synchrotron r…
Emergence of Nearly Flat Bands through an Embedded Kagome Lattice in an Epitaxial Two-dimensional Ge Layer on ZrB2(0001)
Antoine Fleurence, Chi-Cheng Lee, Rainer Friedlein +8
Ge atoms segregating on zirconium diboride thin films grown on Ge(111) were found to crystallize into a two-dimensional bitriangular structure which was recently predicted to be a…
Benchmark of density functional theory for superconductors in elemental materials
Mitsuaki Kawamura, Yuma Hizume, Taisuke Ozaki
Systematic benchmark calculations for elemental bulks are presented to validate the accuracy of density functional theory for superconductors. We developed a method to treat the sp…
Efficient algorithm based on Liechtenstein method for computing exchange coupling constants using localized basis set
Asako Terasawa, Munehisa Matsumoto, Taisuke Ozaki +1
For large-scale computation of the exchange coupling constants , we reconstruct the Liechtenstein formula for localized orbital representation and simplify the energy integ…
Structure map of AB type 2D materials by high-throughput DFT calculations
Masahiro Fukuda, Jingning Zhang, Yung-Ting Lee +1
By high-throughput calculations based on the density functional theory, we construct a structure map for AB type monolayers of 3844 compounds which are all the combinations of…
Hidden mechanism for embedding the flat bands of Lieb, kagome, and checkerboard lattices in other structures
Chi-Cheng Lee, Antoine Fleurence, Yukiko Yamada-Takamura +1
The interplay of hopping parameters that can give rise to flat bands in consequence of quantum interference in electronic, photonic, and other interesting materials has become an e…
OpenMX Viewer: A web-based crystalline and molecular graphical user interface program
Yung-Ting Lee, Taisuke Ozaki
The OpenMX Viewer (Open source package for Material eXplorer Viewer) is a web-based graphical user interface (GUI) program for visualization and analysis of crystalline and molecul…
Efficient O() divide-conquer method with localized natural orbitals
Taisuke Ozaki, Masahiro Fukuda, Gengping Jiang
An efficient O() divide-conquer (DC) method based on localized natural orbitals (LNOs) is presented for large-scale density functional theories (DFT) calculations of gapped and…
Tight-binding calculations of optical matrix elements for conductivity using non-orthogonal atomic orbitals: Anomalous Hall conductivity in bcc Fe
Chi-Cheng Lee, Yung-Ting Lee, Masahiro Fukuda +1
We present a general formula for the tight-binding representation of momentum matrix elements needed for calculating the conductivity based on the Kubo-Greenwood formula using atom…