Y. Harashima

activity

20122024

most citedFirst-principles study on stability and magnetism of NdFe11M and NdFe11MN for M=Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn

82 citations · 534 across the 21 of their papers we have counts for

collaborators

21 papers

cond-mat.mtrl-sci2024

Covariance Linkage Assimilation method for Unobserved Data Exploration

Yosuke Harashima, Takashi Miyake, Ryuto Baba +6

This study proposes a materials search method combining a data assimilation technique based on a multivariate Gaussian distribution with Bayesian optimization. The efficiency of th…

cond-mat.mtrl-sci2023★ 6 cited

Finite temperature effects on the structural stability of Si-doped HfO $_{2}$ using first-principles calculations

Yosuke Harashima, Hiroaki Koga, Zeyuan Ni +9

The structural stabilities of the monoclinic and tetragonal phases of Si-doped HfO $_{2}$ at finite temperatures were analyzed using a computational scheme to assess the effects of…

cond-mat.mtrl-sci2021★ 4 cited

First-principles study on the stability of ( $R$ , Zr)(Fe, Co, Ti) $_{12}$ against 2-17 and unary phases ( $R$ = Y, Nd, Sm)

Taro Fukazawa, Yosuke Harashima, Takashi Miyake

The stability of ( $R$ , Zr)(Fe, Co, Ti) $_{12}$ with a ThMn $_{12}$ structure is investigated using first-principles calculations. We consider energetic competition with multiple phas…

cond-mat.mtrl-sci2021

First-principles investigation of Nd(Fe,M)12 (M = K--Br) and Nd(Fe,Cr,Co,Ni,Ge,As)12: Possible enhancers of Curie temperature for NdFe12 magnetic compounds

Taro Fukazawa, Hisazumi Akai, Yosuke Harashima +1

We investigate the effects of various dopants (M = K--Br) on the Curie temperature of the magnetic compound NdFe12 through first-principles calculations. Analysis by the Korringa--…

cond-mat.mtrl-sci2020★ 7 cited

Spin-wave dispersion and exchange stiffness in Nd $_{2}$ Fe $_{14}$ B and $R$ Fe $_{11}$ Ti ( $R$ =Y, Nd, Sm) from first-principles calculations

Taro Fukazawa, Hisazumi Akai, Yosuke Harashima +1

We theoretically investigate spin-wave dispersion in rare-earth magnet compounds by using first-principles calculations and a method we call the reciprocal-space algorithm (RSA). T…

cond-mat.dis-nn2020★ 1 cited

Analysis of Kohn-Sham Eigenfunctions Using a Convolutional Neural Network in Simulations of the Metal-insulator Transition in Doped Semiconductors

Yosuke Harashima, Tomohiro Mano, Keith Slevin +1

Machine learning has recently been applied to many problems in condensed matter physics. A common point of many proposals is to save computational cost by training the machine with…

cond-mat.mtrl-sci2020★ 18 cited

Data Assimilation Method for Experimental and First-Principles Data: Finite-Temperature Magnetization of (Nd,Pr,La,Ce) $_{2}$ (Fe,Co,Ni) $_{14}$ B

Yosuke Harashima, Keiichi Tamai, Shotaro Doi +8

We propose a data-assimilation method for evaluating the finite-temperature magnetization of a permanent magnet over a high-dimensional composition space. Based on a general framew…

cond-mat.mtrl-sci2020★ 32 cited

Screw dislocation that converts p-type GaN to n-type: Microscopic study on the Mg condensation and the leakage current in p-n diodes

Takashi Nakano, Yosuke Harashima, Kenta Chokawa +9

Recent experiments suggest that Mg condensation at threading dislocations induce current leakage, leading to degradation of GaN-based power devices. To study this issue, we perform…

cond-mat.mtrl-sci2019★ 24 cited

Cerium as a possible stabilizer of ThMn $_{12}$ -type iron-based compounds: A first-principles study

Yosuke Harashima, Taro Fukazawa, Takashi Miyake

The structural stability of CeFe $_{12}$ is investigated by using first-principles calculation. The formation energies of CeFe $_{12}$ relative to the Ce $_{2}$ Fe $_{17}$ + bcc-Fe phas…

cond-mat.mtrl-sci2019★ 46 cited

Bayesian optimization of chemical composition: a comprehensive framework and its application to $R$ Fe $_{12}$ -type magnet compounds

Taro Fukazawa, Yosuke Harashima, Zhufeng Hou +1

We propose a framework for optimization of the chemical composition of multinary compounds with the aid of machine learning. The scheme is based on first-principles calculation usi…

cond-mat.mtrl-sci2018★ 14 cited

Curie temperature of Sm $_{2}$ Fe $_{17}$ and Nd $_{2}$ Fe $_{14}$ B: a first-principles study

Taro Fukazawa, Hisazumi Akai, Yosuke Harashima +1

We calculate intersite magnetic couplings for Sm $_{2}$ Fe $_{17}$ , Nd $_{2}$ Fe $_{14}$ and Nd $_{2}$ Fe $_{14}$ X (X = B, C, N, O, F) using Liechtenstein's formula on the basis of first-principl…

cond-mat.mtrl-sci2018★ 65 cited

Effect of $R$ -site substitution and the pressure on stability of $R$ Fe $_{12}$ : A first-principles study

Yosuke Harashima, Taro Fukazawa, Hiori Kino +1

We theoretically study the structural stability of $R$ Fe $_{12}$ with the ThMn $_{12}$ structure ( $R$ : rare-earth elements, La, Pr, Nd, Sm, Gd, Dy, Ho, Er, Tm, Lu, Y, or Sc, or group…

cond-mat.mtrl-sci2018★ 29 cited

First-principles study of spin-wave dispersion in Sm(Fe $_{1 - x}$ Co $_{x}$ ) $_{12}$

Taro Fukazawa, Hisazumi Akai, Yosuke Harashima +1

We present spin-wave dispersion in Sm(Fe $_{1 - x}$ Co $_{x}$ ) $_{12}$ calculated based on first-principles. Anisotropy in the lowest branch of the spin-wave dispersion around the $Γ$ poin…

cond-mat.mtrl-sci2018★ 32 cited

Role of typical elements in Nd $_{2}$ Fe $_{14}$ $X$ ( $X$ = B, C, N, O, F)

Yasutomi Tatetsu, Yosuke Harashima, Takashi Miyake +1

The magnetic properties and structural stability of Nd $_{2}$ Fe $_{14} X$ ( $X$ = B, C, N, O, F) are theoretically studied by first-principles calculations focusing on the role of $X$ .…

cond-mat.mtrl-sci2017★ 27 cited

First-principles study of inter-site magnetic couplings and Curie temperature in RFe $_{12 - x}$ Cr $_{x}$ (R = Y, Nd, Sm)

Taro Fukazawa, Hisazumi Akai, Yosuke Harashima +1

We present a first-principles study of RFe $_{12 - x}$ Cr $_{x}$ (R = Y, Nd, Sm) crystals with ThMn $_{12}$ structure. We discuss, within the mean field approximation, intersite magnetic…

cond-mat.mtrl-sci2016★ 29 cited

First-principles study of intersite magnetic couplings in NdFe $_{12}$ and NdFe $_{12}$ X (X = B, C, N, O, F)

Taro Fukazawa, Hisazumi Akai, Yosuke Harashima +1

We present a first-principles investigation of NdFe $_{12}$ and NdFe $_{12}$ X (X = B, C, N, O, F) crystals with the ThMn $_{12}$ structure. Intersite magnetic couplings in these compo…

cond-mat.mtrl-sci2016★ 82 cited

First-principles study on stability and magnetism of NdFe11M and NdFe11MN for M=Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn

Yosuke Harashima, Kiyoyuki Terakura, Hiori Kino +2

Recently synthesized NdFe12N has excellent magnetic properties, while it is thermodynamically unstable. Using first-principles method, we study the effect of substitutional 3d tran…

cond-mat.mtrl-sci2015★ 61 cited

Nitrogen as the best interstitial dopant among $X$ =B, C, N, O and F for strong permanent magnet NdFe $_{11}$ Ti $X$ : First-principles study

Yosuke Harashima, Kiyoyuki Terakura, Hiori Kino +2

We study magnetic properties of NdFe $_{11}$ Ti $X$ , where $X$ =B, C, N, O, and F, by using the first-principles calculation based on the density functional theory. Its parent compound…

cond-mat.mtrl-sci2015★ 23 cited

Relevance of $4 f$ - $3 d$ exchange to finite-temperature magnetism of rare-earth permanent magnets: an ab-initio-based spin model approach for NdFe $_{12}$ N

Munehisa Matsumoto, Hisazumi Akai, Yosuke Harashima +2

A classical spin model derived ab initio for rare-earth-based permanent magnet compounds is presented. Our target compound, NdFe $_{12}$ N, is a material that goes beyond today's cha…

cond-mat.dis-nn2013★ 22 cited

Critical exponent of metal-insulator transition in doped semiconductors: the relevance of the Coulomb interaction

Yosuke Harashima, Keith Slevin

We report a simulation of the metal-insulator transition in a model of a doped semiconductor that treats disorder and interactions on an equal footing. The model is analyzed using…

cond-mat.mtrl-sci2012★ 12 cited

Effect of electron-electron interaction near the metal-insulator transition in doped semiconductors studied within the local density approximation

Yosuke Harashima, Keith Slevin

We report a numerical analysis of Anderson localization in a model of a doped semiconductor. The model incorporates the disorder arising from the random spatial distribution of the…

Covariance Linkage Assimilation method for Unobserved Data Exploration

Finite temperature effects on the structural stability of Si-doped HfO2​ using first-principles calculations

First-principles study on the stability of (R, Zr)(Fe, Co, Ti)12​ against 2-17 and unary phases (R = Y, Nd, Sm)

First-principles investigation of Nd(Fe,M)12 (M = K--Br) and Nd(Fe,Cr,Co,Ni,Ge,As)12: Possible enhancers of Curie temperature for NdFe12 magnetic compounds

Spin-wave dispersion and exchange stiffness in Nd2​Fe14​B and RFe11​Ti (R=Y, Nd, Sm) from first-principles calculations

Analysis of Kohn-Sham Eigenfunctions Using a Convolutional Neural Network in Simulations of the Metal-insulator Transition in Doped Semiconductors

Data Assimilation Method for Experimental and First-Principles Data: Finite-Temperature Magnetization of (Nd,Pr,La,Ce)2​(Fe,Co,Ni)14​B

Screw dislocation that converts p-type GaN to n-type: Microscopic study on the Mg condensation and the leakage current in p-n diodes

Cerium as a possible stabilizer of ThMn12​-type iron-based compounds: A first-principles study

Bayesian optimization of chemical composition: a comprehensive framework and its application to RFe12​-type magnet compounds

Curie temperature of Sm2​Fe17​ and Nd2​Fe14​B: a first-principles study

Effect of R-site substitution and the pressure on stability of RFe12​: A first-principles study

First-principles study of spin-wave dispersion in Sm(Fe1−x​Cox​)12​

Role of typical elements in Nd2​Fe14​X (X = B, C, N, O, F)

First-principles study of inter-site magnetic couplings and Curie temperature in RFe12−x​Crx​ (R = Y, Nd, Sm)

First-principles study of intersite magnetic couplings in NdFe12​ and NdFe12​X (X = B, C, N, O, F)

First-principles study on stability and magnetism of NdFe11M and NdFe11MN for M=Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn

Nitrogen as the best interstitial dopant among X=B, C, N, O and F for strong permanent magnet NdFe11​TiX: First-principles study

Relevance of 4f-3d exchange to finite-temperature magnetism of rare-earth permanent magnets: an ab-initio-based spin model approach for NdFe12​N

Critical exponent of metal-insulator transition in doped semiconductors: the relevance of the Coulomb interaction

Effect of electron-electron interaction near the metal-insulator transition in doped semiconductors studied within the local density approximation

Finite temperature effects on the structural stability of Si-doped HfO $_{2}$ using first-principles calculations

First-principles study on the stability of ( $R$ , Zr)(Fe, Co, Ti) $_{12}$ against 2-17 and unary phases ( $R$ = Y, Nd, Sm)

Spin-wave dispersion and exchange stiffness in Nd $_{2}$ Fe $_{14}$ B and $R$ Fe $_{11}$ Ti ( $R$ =Y, Nd, Sm) from first-principles calculations

Data Assimilation Method for Experimental and First-Principles Data: Finite-Temperature Magnetization of (Nd,Pr,La,Ce) $_{2}$ (Fe,Co,Ni) $_{14}$ B

Cerium as a possible stabilizer of ThMn $_{12}$ -type iron-based compounds: A first-principles study

Bayesian optimization of chemical composition: a comprehensive framework and its application to $R$ Fe $_{12}$ -type magnet compounds

Curie temperature of Sm $_{2}$ Fe $_{17}$ and Nd $_{2}$ Fe $_{14}$ B: a first-principles study

Effect of $R$ -site substitution and the pressure on stability of $R$ Fe $_{12}$ : A first-principles study

First-principles study of spin-wave dispersion in Sm(Fe $_{1 - x}$ Co $_{x}$ ) $_{12}$

Role of typical elements in Nd $_{2}$ Fe $_{14}$ $X$ ( $X$ = B, C, N, O, F)

First-principles study of inter-site magnetic couplings and Curie temperature in RFe $_{12 - x}$ Cr $_{x}$ (R = Y, Nd, Sm)

First-principles study of intersite magnetic couplings in NdFe $_{12}$ and NdFe $_{12}$ X (X = B, C, N, O, F)

Nitrogen as the best interstitial dopant among $X$ =B, C, N, O and F for strong permanent magnet NdFe $_{11}$ Ti $X$ : First-principles study

Relevance of $4 f$ - $3 d$ exchange to finite-temperature magnetism of rare-earth permanent magnets: an ab-initio-based spin model approach for NdFe $_{12}$ N