I apply state-of-the-art methods that combine statistical physics and information-theoretic perspectives with the power of supercomputers to unsolved problems in interacting many-body systems and information science.
Research Interests
tensor network
computational physics
quantum Monte Carlo
quantum phase transition
magnetic material
condensed matter physics
statistical physics
Research Areas
Informatics, Computational science
Natural sciences, Mathematical physics and basic theory
Papers
Neural network approach to scaling analysis of critical phenomena
Ryosuke Yoneda; Kenji Harada
Physical Review E, 27 Apr. 2023, Peer-reviewed
Quantum critical dynamics in the two-dimensional transverse Ising model
Chisa Hotta; Tempei Yoshida; Kenji Harada
Physical Review Research, 17 Mar. 2023, Peer-reviewed
Automatic structural optimization of tree tensor networks
Meeting Abstracts of the Physical Society of Japan, 2019
Entanglement branching operator
Kenji Harada
Physical Review B, 16 Jan. 2018, Peer-reviewed
Quantum phase transition of SU(N) generalized Heisenberg model on square lattice: necessary condition by conformal bootstrap method, emergent SO(5) symmetry
Harada Kenji; Okubo Tsuyoshi; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2016
SU(N) Heisenberg model with multicolumn representations
Tsuyoshi Okubo; Kenji Harada; Jie Lou; Naoki Kawashima
PHYSICAL REVIEW B, Oct. 2015, Peer-reviewed
Kernel method for corrections to scaling
Kenji Harada
PHYSICAL REVIEW E, Jul. 2015, Peer-reviewed
Thermal phase transition of generalized Heisenberg models for SU(N) spins on square and honeycomb lattices
Numerical study of incommensurability of the spiral state on spin-1/2 spatially anisotropic triangular antiferromagnets using entanglement renormalization
Kenji Harada
PHYSICAL REVIEW B, Nov. 2012, Peer-reviewed
多体問題におけるテンソルネットワーク法
原田 健自
RIMS研究集会報告書, 2012, Invited
Bayesian inference in the scaling analysis of critical phenomena
Kenji Harada
PHYSICAL REVIEW E, Nov. 2011, Peer-reviewed
Diffusion in the continuous-imaginary-time quantum world-line Monte Carlo simulations with extended ensembles
Kenji Harada; Yuto Kuge
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Jan. 2008, Peer-reviewed
Dimer-quadrupolar quantum phase transition in the quasi-one-dimensional Heisenberg model with biquadratic interaction
Kenji Harada; Naoki Kawashima; Matthias Troyer
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Jan. 2007, Peer-reviewed
Quantum world-line Monte Carlo method with non-binary loops and its application
K. Harada
Computer Simulation Studies in Condensed-Matter Physics XVIII, 2006
Phase diagram of the S=1 bilinear biquadratic model
Kenji Harada; Naoki Kawashima; Matthias Troyer
LOW TEMPERATURE PHYSICS, PTS A AND B, 2006, Peer-reviewed
Recent Developments of Quantum Monte Carlo Methods
Harada Kenji
Bulletin of the Japan Society for Industrial and Applied Mathematics, 2005, Peer-reviewed, Invited
Recent developments of world-line Monte Carlo methods
N Kawashima; K Harada
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Jun. 2004, Peer-reviewed, Invited
Quantum Monte Carlo algorithm for softcore boson systems
J Smakov; K Harada; N Kawashima
PHYSICAL REVIEW E, Oct. 2003, Peer-reviewed
Neel and spin-peierls ground states of two-dimensional SU(N) quantum antiferromagnets
K Harada; N Kawashima; M Troyer
PHYSICAL REVIEW LETTERS, Mar. 2003, Peer-reviewed
Coarse-grained loop algorithms for Monte Carlo simulation of quantum spin systems
Kenji Harada; Naoki Kawashima
Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, 26 Nov. 2002, Peer-reviewed
Coarse-grained loop algorithms for Monte Carlo simulation of quantum spin systems
K Harada; N Kawashima
PHYSICAL REVIEW E, Nov. 2002, Peer-reviewed
Quadrupolar order in isotropic Heisenberg models with biquadratic interaction
K Harada; N Kawashima
PHYSICAL REVIEW B, Feb. 2002, Peer-reviewed
Quadrupolar order in the quantum XY model with cubic anisotropy
K Harada; N Kawashima
PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT, 2002, Peer-reviewed
Classical correlation-length exponent in the nonuniversal quantum phase transition of a diluted Heisenberg antiferromagnet
C Yasuda; S Todo; K Harada; N Kawashima; S Miyashita; H Takayama
PHYSICAL REVIEW B, Apr. 2001, Peer-reviewed
Loop algorithm for Heisenberg models with biquadratic interaction and phase transitions in two dimensions
K Harada; N Kawashima
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Jan. 2001, Peer-reviewed
Short-time dynamics and magnetic critical behavior of the two-dimensional random-bond Potts model
HP Ying; K Harada
PHYSICAL REVIEW E, Jul. 2000, Peer-reviewed
Quantum phase transition of the randomly diluted Heisenberg antiferromagnet on a square lattice
K Kato; S Todo; K Harada; N Kawashima; S Miyashita; H Takayama
PHYSICAL REVIEW LETTERS, May 2000, Peer-reviewed
Quantum phase transition of two-dimensional diluted Heisenberg antiferromagnet
S Todo; C Yasuda; K Kato; K Harada; N Kawashima; S Miyashita; H Takayama
PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT, 2000, Peer-reviewed
Quantum Monte Carlo study of site-diluted Heisenberg antiferromagnet on a square lattice
S Todo; K Kato; H Takayama; K Harada; N Kawashima; S Miyashita
INTERNATIONAL JOURNAL OF MODERN PHYSICS C, Dec. 1999, Peer-reviewed
Kosterlitz-Thouless transition of quantum XY model in two dimensions
K Harada; N Kawashima
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Aug. 1998, Peer-reviewed
Numerical Study of Quantum Spin Models by Loop Algorithm
Kenji Harada
Kyoto university, May 1998, Peer-reviewed
The two-dimensional S=1 quantum Heisenberg antiferromagnet at finite temperatures
K Harada; M Troyer; N Kawashima
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Apr. 1998, Peer-reviewed
Universal jump in the helicity modulus of the two-dimensional quantum XY model
K Harada; N Kawashima
PHYSICAL REVIEW B, May 1997, Peer-reviewed
Universal jump in the helicity modulus of the two-dimensional quantum XY model
Kenji Harada; Naoki Kawashima
Physical Review B - Condensed Matter and Materials Physics, 1997, Peer-reviewed
Misc.
Finite-size scaling with a relevant field using the parallelizable multi-worm algorithm
Masaki Akiko; Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2017
22pEH-9 Entanglement renormalization of frustrated quantum magnets
Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2010
26pQK-8 Numerical search of ground states based on tensor product representation II
Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2009
30pTJ-10 Numerical search of ground states based on tensor product representation
Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2009
22aVA-12 Quantum Phase Transition in the Quasi-One-Dimensional SU(N) models
Harada K.; Kawashima N.; Troyer Matthias
Meeting Abstracts of the Physical Society of Japan, 2008
25pPSA-14 Quantum Extended Monte Carlo Simulations for Valence Bond Solid States
Harada K.; Kawashima N.
Meeting Abstracts of the Physical Society of Japan, 2008
19aWA-8 Quantum Monte Carlo simulations for Heisenberg model with 4-site interactions
Tsukamoto Mitsuaki; Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2007
24aTL-11 Extended Ensemble QMC SImulations for Nematic-VBS Phase Transition
Harada K.; Kawashima N.; Troyer Matthias
Meeting Abstracts of the Physical Society of Japan, 2007
27aXG-7 Ground States of SU (N) Quantum Antiferromagnets
Tanabe Y.; Harada K.; Kawashima N.
Meeting Abstracts of the Physical Society of Japan, 2006
21aXL-7 Ground state in anisotropic two-dimensional S=1 bi-linear bi-quad ratio models
Harada K.; Kawashima N.; Troyer M.
Meeting Abstracts of the Physical Society of Japan, 2005
14aTB-9 Quantum phase tiansition of the S=1 bi-linear bi-quadiatic model in one and two dimensions
Harada K; Kawashima N; Troyer Matthias
Meeting Abstracts of the Physical Society of Japan, 2004
29pWM-3 Quantum phase transition of quasi-1-dimentional S=1 bi-linear bi-quadratic model
Harada Kenji; Kawashima Naoki; Troyer Matthias
Meeting Abstracts of the Physical Society of Japan, 2004
29pPSA-60 Multicanonical Method for Two-dimensional Hard-disk System
Umegaki Yoshiyuki; Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2004
Coarse-grained loop algorithm for the easy-plane antiferromagnetic Heisenberg model in magnetic fields
Tanioka Yoshihiko; Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2003
Critical slowing down in Monte Carlo simulations using worm and coarse-grained loop algorithms
Harada Kenji; Kawashima Naoki; Smakov Jurij
Meeting Abstracts of the Physical Society of Japan, 2003
A new formulation of the coarse-grained algorithm for QMC
Kawashima Naoki; Harada Kenji
Meeting Abstracts of the Physical Society of Japan, 2003
Quadrupole order in a quantum XY model with cubic anisotropy
Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2001
Quantum Monte Carlo simulation of Heisenberg model with biquadratic interaction
Kawashima Naoki; Harada Kenji
Meeting Abstracts of the Physical Society of Japan, 2001
Improved estimator in loop algorithm
Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2000
Loop Algorithm for Quantum Helsenberg Antiferromagnet in Magnetic Field
HARADA Kenji; KAWASHIMA Naoki
Meeting Abstracts of the Physical Society of Japan, 1998
Meeting Abstracts of the Physical Society of Japan, 2016
20aAC-5 Binder parameters of the classical Heisenberg model with Ising-like Anisotropy
Watanabe H.; Kawashima N.; Harada K.
Meeting Abstracts of the Physical Society of Japan, 2012
26aTE-10 Incommensurate spiral phase of the S=1/2 antiferro-Heisenberg model on a spatial anisotropic triangular lattice
Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2011
21pGA-6 Variational study of frustrated quantum Heisenberg antiferromagnet on anisotropic triangular lattice with MERA
Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2011
25pTE-3 MERA calculations of the anisotropic triangular Heisenberg antiferromagnets
Harada Kenji; Kawashima Naoki
Meeting Abstracts of the Physical Society of Japan, 2010
25pXD-2 Ground state in anisotropic two-dimensional S=1 bi-linear bi-quadratic models
Harada K.; Kawashima N.; Troyer Matthias
Meeting Abstracts of the Physical Society of Japan, 2006
10aAY-6 Kernel Method for Corrections to Scaling
Harada Kenji
Meeting abstracts of the Physical Society of Japan, 22 Aug. 2014
27pAK-9 A Bayesian framework for the scaling analysis of critical phenomena with irrelevant scaling operators
Harada Kenji
Meeting abstracts of the Physical Society of Japan, 05 Mar. 2014
Magnetic orders in S=1/2 Antiferromagnetic Heisenberg model on the Shastry-Sutherland lattice
Lou Jie; Suzuki T.; Harada K.; Kawashima N.
Meeting abstracts of the Physical Society of Japan, 26 Aug. 2013
20pAC-13 Quantum Phase Transition Between Neel and Z_3 VBS on Honeycomb Lattices
Harada Kenji
Meeting abstracts of the Physical Society of Japan, 24 Aug. 2012
26pAG-7 Dimerlization of Generalized Quantum Heisenberg Model on Honeycomb Lattice
Harada Kenji
Meeting abstracts of the Physical Society of Japan, 05 Mar. 2012
Neel and Spin-Peierls ground states of two-dimensional SU(N) quantum antiferromagnets
Harada Kenji; Kawashima Naoki; Matthias Troyer
Meeting abstracts of the Physical Society of Japan, 06 Mar. 2003
Worm Algorithm and Loop Algorithm for Quantum Monte Carlo(S>1/2)
Kawashima Naoki; Harada Kenji
Meeting abstracts of the Physical Society of Japan, 13 Aug. 2002
24aWL-4 Quantum Monte Carlo study of SU(N) model in two dimensions
Harada Kenji; Kawashima Naoki
Meeting abstracts of the Physical Society of Japan, 01 Mar. 2002
26pXY-5 LANL C.Batista, LANL J.E.GubernatisDoes the Chubukov phase exist in the one-dimensional bilinear-biquadratic model?
Kawashima Naoki; Harada Kenji
Meeting abstracts of the Physical Society of Japan, 01 Mar. 2002
26aT-7 Ground-State Phase Transition of Two-Dimensional Diluted Antiferromagnetic Heisenberg Model III : Behavior of Correlation Length near Transition Concentration
YASUDA C; TODO S; TAKAYAMA H; HARADA K; KAWASHIMA N; MIYASHITA S
Meeting abstracts of the Physical Society of Japan, 03 Sep. 1999
29p-XE-16 Ground-State Phase Transition of Two-Dimensional Diluted Antiferromagnetic Heisenberg Model II : Finite Size Scaling Study near Percolation Threshold
Harada K.; Kawashima N.; Kato K.; Todo S.; Takayama H.; Miyashita S.
Meeting abstracts of the Physical Society of Japan, 15 Mar. 1999
29p-XE-15 Ground-State Phase Transition of Two-Dimensional Diluted Antiferromagnetic Heisenberg Model I. : Quantum Monte Carlo Analysis
Kato K.; Todo S.; Takayama H.; Harada K.; Kawashima N.; Miyashita S.
Meeting abstracts of the Physical Society of Japan, 15 Mar. 1999
10pAQ-4 Generalized Jordan-Wigner transformation and Z_2×Z_2 symmetry
Okunishi Kouichi; Harada Kenji
Meeting abstracts of the Physical Society of Japan, 22 Aug. 2014
10pAQ-5 Quantum Monte Carlo Study of Quantum Criticality and String Order on SO(N) Bilinear-Biquadratic Spin Chains
Harada Kenji; Okunishi Kouichi
Meeting abstracts of the Physical Society of Japan, 22 Aug. 2014
28pAK-15 Thermal phase transitions of the generalized SU (N) Heisenberg model on square and honeycomb lattices
Suzuki T.; Harada K.; Matsuo H.; Todo S.; Kawashima N.
Meeting abstracts of the Physical Society of Japan, 05 Mar. 2014
28pAK-14 Deconfined criticality and two length scales of SU(N) J-Q model
Okubo T.; Harada K.; Suzuki T.; Matsuo H.; Lou Jie; Watanabe H.; Todo S.; Kawashima N.
Meeting abstracts of the Physical Society of Japan, 05 Mar. 2014
Negative sign problem in bilinear-biquadratic chain II
Okunishi Kouichi; Harada Kenji
Meeting abstracts of the Physical Society of Japan, 26 Aug. 2013
Parallelized Quantum Monte Carlo Algorithm with Non-local Worm Update
Masaki A.; Suzuki T.; Harada K.; Todo S.; Kawashima N.
Meeting abstracts of the Physical Society of Japan, 26 Aug. 2013
Numerical study of deconfined criticality on the two-dimensional SU(N) J-Q models
Harada K.; Suzuki T.; Okubo T.; Matsuo H.; Lou Jie; Watanabe H.; Todo S.; Kawashima N.
Meeting abstracts of the Physical Society of Japan, 26 Aug. 2013
Qunatum Monte Carlo study on the ground state of the square lattice SU(N)model
Okubo T.; Harada K.; Suzuki T.; Matsuo H.; Lou Jie; Watanabe H.; Todo S.; Kawashima N.
Meeting abstracts of the Physical Society of Japan, 26 Aug. 2013
28pXZC-9 Negative sign problem in bilinear-biquadratic chain
Okunishi Kouichi; Harada Kenji
Meeting abstracts of the Physical Society of Japan, 26 Mar. 2013
29aXZD-8 Universality of deconfined quantum criticality
Harada K.; Suzuki T.; Matsuo H.; Okubo T.; Masaki A.; Watanabe H.; Todo S.; Kawashima N.
Meeting abstracts of the Physical Society of Japan, 26 Mar. 2013
29aXZD-9 Finite-temperature Transition of SU(N) Heisenberg model on a square lattice
Suzuki T.; Harada K.; Matsuo H.; Todo S.; Kawashima N.
Meeting abstracts of the Physical Society of Japan, 26 Mar. 2013
29aXZD-11 Parallelization of the Worm Algorithm
Masaki A.; Kawashima N.; Todo S.; Harada K.; Suzuki T.
Meeting abstracts of the Physical Society of Japan, 26 Mar. 2013
Study of the Shastry Sutherland Model Using Multi-scale Entanglement Renormalization Ansatz
Jie Lou; Takafumi Suzuki; Kenji Harada; Naoki Kawashima
10 Dec. 2012
Quantum Monte Carlo Simulation of S=1/2 Heisenberg model with Four Spin Interaction
M. Tsukamoto; K. Harada; N. Kawashima
25TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT25), PART 4, 2009, Peer-reviewed
Coarse-grained loop algorithms for Monte Carlo simulation of quantum spin systems (vol E 66, art no 056705, 2002)
K Harada; N Kawashima
PHYSICAL REVIEW E, Mar. 2003
Presentations
テンソルネットワークによるニューラルネットワークモデルの圧縮
原田健自
第4回 力学系の視点からの脳・神経回路の理解, 02 Dec. 2022, Invited
Compressing neural networks by tensor networks
Kenji Harada
ipi seminar, University of Tokyo, 24 Nov. 2022, Invited
Tensor renormalization group study of the non-equilibrium critical fixed point of the one-dimensional contact process
Kenji Harada
The 15th Asia Pacific Physics Conference (APPC15), 26 Aug. 2022, Invited
Novel Quantum States in Condensed Matter 2017, 06 Nov. 2017, YITP, Kyoto University, Invited
繰り込み群とテンソルネットワーク
原田 健自
日本物理学会 第72回年次大会 領域11、領域3、素粒子論領域合同シンポジウム「テンソルネットワーク法とその可能性」, 18 Mar. 2017, 日本物理学会, Invited
General Entanglement Branching in a Tensor Network
Kenji Harada
Fourth Workshop on Tensor Network States: Algorithms and Applications, 14 Dec. 2016, National Center for Theoretical Sciences, Hsinchu, Taiwan, Invited
Branching and tensor network
Kenji Harada
International Workshop on Tensor Networks and Quantum Many-Body Problems (TNQMP2016), 27 Jun. 2016, ISSP, University of Tokyo, Invited
Negative sign problem and topological order in a quantum chain
Kenji Harada
Quantum Computation and Machine Learning Seminar Series, 16 Mar. 2016, 早稲田大学, Invited
日本物理学会 第70回年次大会 シンポジウム「『京』が拓いた物性物理」, 22 Mar. 2015, 日本物理学会, Invited
Quantum Monte Carlo study of Quantum Criticality on SO(N) Bilinear-biquadratic Chains
Kenji Harada
International Workshop on New Frontier of Numerical Methods for Many-Body Correlations ― Methodologies and Algorithms for Fermion Many-Body Problems, 18 Feb. 2015, CMSI
Quantum Monte Carlo study of Quantum Criticality on SO(N) Bilinear Biquadratic Chains
Kenji Harada
the 9th International Conference on Computational Physics (ICCP9), 07 Jan. 2015, National University of Singapore
Numerical study of quantum frustrated magnets using entanglement renormalization: spin-1/2 spatially anisotropic triangular antiferromagnets and Shastry-Sutherland model
原田 健自
基研研究会「量子スピン系の物理」, 13 Nov. 2012, 京都大学基礎物理学研究所
Numerical study of quantum frustrated magnets using entanglement renormalization
Kenji Harada
International Workshop on Cooperative Quantum Dynamics and Its Control (CQDC'12), 08 Nov. 2012, Jeulich super computer center, Jeulich, Germany, Invited
Numerical study of incommensurability of the spiral state on spin-1/2 spatially anisotropic triangular antiferromagnets using entanglement renormalization"
Kenji Harada
Conference on Computational Physics (CCP2012) for Physics, Chemistry, Biology, Engineering and related academic fields and industrial applications, 15 Oct. 2012
Bayesian Inference in the Scaling Analysis of Critical Phenomena
Kenji Harada
International Workshop on Recent Developments of Studies on Phase Transitions 2012, 19 Jun. 2012, University of Tokyo, Invited
Magnetic Structure of Ground States in Spatially Anisotropic Triangular Antiferromagnets
Kenji Harada
the 26th Nishinomiya-Yukawa Memorial International Workshop "Novel Quantum States in Condensed Matter 2011 (NQS2011)", 08 Nov. 2011, YITP, Kyoto Univ.
エンタングルメントと繰り込み:フラストレーションのある量子磁性体の基底状態計算
原田 健自
物性科学領域横断研究会, 28 Nov. 2010, 東京大学
Entanglement renormalization on the triangular lattice
Kenji Harada
New Development of Numerical Simulations in Low-Dimensional Quantum Systems: From Density Matrix Renormalization Group to Tensor Network Formulations, Oct. 2010, YITP, Kyoto University
Entanglement renormalization of quantum frustrated magnets
Kenji Harada
Japan-Swiss Joint Workshop: New Trends in Theory of Correlated Materials, Sep. 2010, ISSP, Univ. of Tokyo, Invited
Multi-scale Entanglement Renormalization on a Triangular Lattice
Kenji Harada
Miniworkshop on Tensor Network Based Numerical Methods (Numerical Methods in Strongly Correlated Physics), 28 May 2010, Nathional Center for Theoretical Sciences, National Tsing Hua University, Hsinchu, Taiwan
Quadrupolar order in the bilinear-biquadratic model
Kenji Harada
Academia Sinica seminar, 25 May 2010, Academina Sinica
フラストレートした量子スピン系のマルチスケールエンタングルメント繰り込み(MERA)
原田 健自
基研セミナー, 30 Mar. 2010, 京都大学基礎物理学研究所
フラストレートした量子スピン系のマルチスケールエンタングルメント繰り込み(MERA)
原田 健自
次世代スパコン物性科学分野研究会「新物質とエネルギー」, 10 Mar. 2010, 東京大学物性研究所
Numerical study of quantum frustrated systems by tensor network methods
Grant-in-Aid for Scientific Research (C)
Kyoto University
Kenji HARADA
From 01 Apr. 2011, To 31 Mar. 2014, Project Closed
テンソルネットワーク;フラストレーション;量子スピン系;MERA;スケーリング解析;ベイズ推定;トポロジカル秩序;非局所ユニタリー変換;Valence bond solid;SU(N) JQモデル;SO(N) BLBQモデル;量子モンテカルロ法;負符号問題;対称性で保護されたトポロジカル秩序;エンタングルメント繰り込み;反強磁性ハイゼンベルグモデル;シャストリー・サザーランド格子;変分法;プラケットダイマー相;磁化プラトー;コード開発フレームワーク;反強磁性ハイゼンベルグ;三角格子;スパイラル;非整合