Research interest

Developing and applying first-principle and numerical methods, along with machine learning models, to solve complex scientific problems using computer-based simulations.

Machine learning (ML) and Optimization

  • Developing methodology and applying interatomic machine learning potentials for predicting atomic interactions, structures, dynamics, and reactions.
  • On-the-fly ML+MC for accelaing MC sampling
  • Supervised and unsupervised learning for physics problems

Condensed matter physics

Machine learning-based numerical simulations, integration of machine learning into scientific modeling, empirical modeling for large-scale simulations, development of methodology based on first-principles physics, numerical optimization methods for understanding experimental phenomena, and software development for experimental orchestration are among the research scopes in this field. These areas can potentially contribute to solving complex scientific problems in materials science, chemistry, and physics.

Experiences

Research scientist

2021.09 - Present
Samsung Semiconductor

Combining machine learning and physics to accelerate atomic simulations. Developing first-principles methods for studying both physical properties and chemical reactions.

Postdoc researcher

2018.09 - 2021.08
KAIST (Brain Korea (BK) 21 Fellowship)

First-principles method developments and develop machine learning algorithms for physics.

Joint Development Project (KAIST-Samsung)

2015.05 – 2016.04
KAIST-Samsung

Method development for accelerating e-Beam Monte-Carlo simulation.

Venture Research Programs for MS and PhD Students

2017.03 - 2018.02
College of Natural Sciences

Venture Research Programs for MS and PhD Students

2016.03 - 2017.02
College of Natural Sciences

Hubbard U calculation through machine learning.

Undergraduate visiting research program (Cavendish-KAIST Collaboration)

2006.06 - 2006.08
Cavendish Laboratory, University of Cambridge

Compensate e-Beam scattering proximity effect by inverse function design with Monte Carlo.

Presentation & Awards

Outstanding presentation awards

Duk Joo Kim Young Scientist Award, - Korean Physical Society, (2020).
Jx; An open-source software to calculate magnetic coupling constant and matrix, - KIAS, Poster (2019)
Analytic continuation via “domain knowledge free” machine learning, - APCTP-KIAS:Quantum Materials Symposium 2018, Poster (2018).
Analytic continuation via “domain knowledge free” machine learning, - KPS2018 Spring, Contributed talk (2018)
9 th Summer school on ‘Scientific Computing and Machine Learning’, - KIAS-CAC (2018)
Reliability and applicability of magnetic force linear response theory; Numerical parameters, predictability, and orbital resolution, - 10th BK21 Young Physicists Workshop, Poster (2018)
Reliability and applicability of magnetic force linear response theory; Numerical parameters, predictability, and orbital resolution, - KPS2017 Fall, Contributed talk (2017)
Orbital resolved exchange interactions combined with QSGW self energy. - KIAS, Poster (2017)

Invited talks

On-the-fly accelerating Monte Carlo simulations with XAI - Seoul National University of Science and Technology, Seoul (2021.08)
Reliably accelerating Monte Carlo simulations with XAI - Machine Learning on Condensed Matter physics APCTP, (2021.08)
Analysis and debugging of material informatics using tools - 2021 Summer Material Informatics Convergence Education Program, (2021.08)
Reliably accelerating Monte Carlo simulations with XAI - PCS-IBS, Deajeon (2021.08)
Explainable AI (XAI) for scientific computing. - Korea Institute for Advanced Study (KIAS), Seoul (2021.06.16)
Computational method developments for material science (Machine learning, first-principles method development & more). - Korea Institute of Science and Technology (KIST), Seoul (2020.11.25)
Method development for numerical condensed matter physics; Jx, the magnetic exchange interactions and accelerated analytic continuation via machine learning, - Kyungpook National University., Daegu (2020.01.30)
Machine learning for numerical condensed matter physics; analytic continuation and Monte Carlo sampling, - Kangwon National Univ., Chuncheon (2020.01.21)
Machine learning for numerical condensed matter physics; analytic continuation and Monte Carlo sampling, - POSTECH, Pohang (2019.12)
First principles based methodologies for correlated materials magnetic force theory and analytic continuation, - 5th Workshop on Supercomputing for Computational Bio/Nano/Materials Science, Daejeon (2019.7)
Analytic continuation via “domain-knowledge free” machine learning, - PCS-IBS, Daejeon (2019.3)
Analytic continuation via domain-knowledge free machine learning, - KPS 2018Fall. Focus sessions AI (artificial intelligence) techniques for condensed matter physics and material science II (2018.10)
Analytic continuation via “domain-knowledge free” machine learning, - KIAS-Comp.Sciences, Seoul (2018.6)
Reliability and applicability of magnetic force linear response theory; Numerical parameters, predictability, and orbital resolution with OpenMX, - ISSP-The University of Tokyo (2018.7.10)

Recent presentations

On-the-fly machine learning algorithm for accelerating Monte Carlo sampling; Application to the stochastic analytical continuation, - APS march meeting, Boston (2020.03), Contributed talk
On-the-fly machine-learning algorithm for accelerating Monte Carlo sampling; Application to the stochastic analytical continuation, - KPS, (2019.10), Contributed talk
Jx; An open-source software to calculate magnetic coupling constant and matrix - Asian 22, Osaka (2019.10), Poster
Analytic continuation via domain-knowledge free machine learning, - APS march meeting, Boston (2019.03), Contributed talk
Analytic continuation via domain-knowledge free machine learning, - Kavli Institute for Theoretical Physics, (2019.02), Poster
First-principles calculation of Heisenberg exchange coupling and branching ratio, International Workshop on Superconductivity and Related Functional Materials - (NIMS), Japan (2016.12), Poster
Analytic continuation via domain-knowledge free machine learning - Materials Research Society, Boston (2018.11), Poster

Publications

Google scholar link
  • (invited review in Korean) New material design search using density functional theory and machine learning.
  • Hongkee Yoon, Hyunggeun Lee, Yoon Gu Kang, and Myung Joon Han.
    Electrical and Electronic Materials (submitted), 2020.
  • Jx; An open-source software for calculating magnetic interactions based on magnetic force theory.
  • Hongkee Yoon, Taek Jung Kim, Jae-Hoon Sim, and Myung Joon Han.
    Comput. Phys. Commun., 247:106927, February 2020.
  • Induced Magnetic Two-dimensionality by Hole Doping in Superconducting NdxSr1-xNiO2.
  • Siheon Ryee* , Hongkee Yoon* , Taek Jung Kim*, Min Yong Jeong and Myung Joon Han.
    Phys. Rev. B, 101:064513, February 2020, *these authors are equally contributed.
  • Magnetic force theory combined with quasi-particle self-consistent GW method.
  • Hongkee Yoon, Seung Woo Jang, Jae-Hoon Sim, Takao Kotani, and Myung Joon Han.
    Journal of Physics Condensed Matter, 31(40):405503, October 2019.
  • Reliability and applicability of magnetic-force linear response theory; Numerical parameters, predictability, and orbital resolution.
  • Hongkee Yoon, Taek Jung Kim, Jae-Hoon Sim, Seung Woo Jang, Taisuke Ozaki, and Myung Joon Han.
    Phys. Rev. B, 97(12):125132, March 2018.
  • Analytic continuation via domain knowledge free machine learning.
  • Hongkee Yoon, Jae-Hoon Sim, and Myung Joon Han.
    Phys. Rev. B, 98(24):245101, December 2018.
  • Observation of the thermal influenced quantum behaviour of water near a solid interface.
  • Hongkee Yoon and Byoung Jip Yoon.
    Scientific Reports, 8(1):7016, May 2018
  • On the origin and the manipulation of ferromagnetism in Fe3GeTe2; Defects and dopings.
  • Seung Woo Jang, Min Yong Jeong, Hongkee Yoon, Siheon Ryee, and Myung Joon Han.
    arXiv:1904.04510 [cond-mat], April 2019 (under review).
  • Calculating magnetic interactions in organic electrides.
  • Taek Jung Kim, Hongkee Yoon, and Myung Joon Han.
    Phys. Rev. B, 97(21):214431, June 2018.
  • Calculating branching ratio and spin-orbit coupling from first principles; A formalism and its application to iridates.
  • Jae-Hoon Sim, Hongkee Yoon, Sang Hyeon Park, and Myung Joon Han.
    Physical Review B, 94(11), September 2016.
  • First-principles-based calculation of branching ratio for 5d, 4d, and 3dtransitionmetal systems.
  • Do Hoon Keim, Jae-Hoon Sim, Hongkee Yoon, and Myung Joon Han
    JPCM accepted, February 2020.
  • Microscopic understanding of magnetic interactions in bilayer CrI3. Phys. Rev. Materials,
  • Seung Woo Jang, Min Yong Jeong, Hongkee Yoon, Siheon Ryee, and Myung Joon Han.
    Phys. Rev. Materials, 3(3):031001, March 2019.
  • Charge density functional plus U theory of LaMnO3
  • Seung Woo Jang, Siheon Ryee, Hongkee Yoon, and Myung Joon Han.
    Phys. Rev. B, 98(12):125126, September 2018.
  • Charge density functional plus U calculation of lacunar spinel GaM4Se8(M = Nb, Mo, Ta, and W).
  • Hyunggeun Lee, Min Yong Jeong, Jae-Hoon Sim, Hongkee Yoon, Siheon Ryee, and Myung Joon Han.
    EPL, 125(4):47005, February 2019.
  • Anomalous behavior of the quasi-one-dimensional quantum material Na2OsO4 at high pressure.
  • R. Sereika, K. Yamaura, Y. Jia, S. Zhang, C. Jin, H. Yoon, M. Y. Jeong, M. J. Han, D. L. Brewe, S. M. Heald, S. Sinogeikin, Y. Ding, and H. k. Mao.
    Materials Today Physics, 8:18–24, March 2019.
  • Modified Granato–Lucke Theory with Pinning Length Distribution in Solid 4He.
  • Evan S. H. Kang, Hongkee Yoon, and Eunseong Kim.
    J. Phys. Soc. Jpn., 84(3):034602, February 2015.
  • Parallel polymer tandem solar cells containing comb-shaped common electrodes.
  • Hee Yoon Han, Hongkee Yoon, and Choon Sup Yoon.
    Solar Energy Materials and Solar Cells, 132:56–66, January 2015.

    In Preparation

    On-the-fly machine learning algorithm for accelerating Monte Carlo sampling; Application to the stochastic analytical continuation.
    Hongkee Yoon and Myung Joon Han.
    in Preparation.

    Codes

    Jx: the open-source MFT(magnetic force theory) code