RESEARCH

From various viewpoints, I have studied topological aspects of condensed matter physics, such as proposing chiral magnetic ordering (triple-Q state) associated with topological Hall effect and ferrimagnetic state with semimetallic Dirac electrons in spin-charge coupled systems, and novel topological defects (excitations/solitons) in quantum spin systems. I have also developed and improved numerical methods for computing topological invariants in disordered systems based on noncommutative geometry and determination of topological phases via machine learning.

The purpose of my research on this project is to make a machine determining topological phases which can be used without deep knowledge about topological physics, and to show the versatility of the machine. In order to achieve the goal, I will deal with topological phases that break translational symmetry and many-body topological phases, which are usually difficult to identify.

EDUCATION

2009

Bachelor Degree in Physics, Department of Physics, Tokyo Institute of Technology

2011

Master Degree in Engineering, Department of Applied Physics, Graduate School of Engineering, The University of Tokyo

2014

Ph.D. in Engineering, Department of Applied Physics, Graduate 2015 School of Engineering, The University of Tokyo

PROFESSIONAL EXPERIENCE

2015

Postdoctoral Scholar, Okinawa Institute of Science and Technology Graduate University (OIST)

2015

-Present Assistant Professor, Department of Physics, The University of Tokyo

HONORS AND AWARDS

2020

The 25th Outstanding Paper Award of the Physical Society of Japan

SELECTION OF PUBLICATIONS

"Spin Chirality Ordering and Anomalous Hall Effect in the Ferromagnetic Kondo Lattice Model on a Triangular Lattice"
Yutaka Akagi and Yukitoshi Motome,
Journal of the Physical Society of Japan 79, 083711-1-4 (Aug. 2010).
DOI: 10.1143/JPSJ.79.083711

"Hidden Multiple-spin Interactions as an Origin of Spin Scalar Chiral Order in Frustrated Kondo Lattice Models"
Yutaka Akagi, Masafumi Udagawa, and Yukitoshi Motome,
Physical Review Letters 108, 096401-1-5 (Feb. 2012).
DOI: 10.1103/PhysRevLett.108.096401

"Effect of Quantum Spin Fluctuation on Scalar Chiral Ordering in the Kondo Lattice Model on a Triangular Lattice"
Yutaka Akagi, Masafumi Udagawa, and Yukitoshi Motome,
Journal of the Physical Society of Japan 82, 123709-1-4 (Nov. 2013).
DOI: 10.7566/JPSJ.82.123709

"Reconstruction of Chiral Edge States in a Magnetic Chern Insulator"
Ryo Ozawa, Masafumi Udagawa, Yutaka Akagi, and Yukitoshi Motome,
Journal of the Physical Society of Japan 83, 073706-1-4 (Jun. 2014).
https://doi.org/10.7566/JPSJ.83.073706

"Spontaneous formation of kagome network and Dirac half-semimetal on a triangular lattice"
Yutaka Akagi and Yukitoshi Motome,
Physical Review B 91, 155132-1-10 (Apr. 2015).
DOI: 10.1103/PhysRevB.91.155132

"Quantum solitons with emergent interactions in a model of cold atoms on the triangular lattice"
Hiroaki T. Ueda, Yutaka Akagi, and Nic Shannon,
Physical Review A 93, 021606(R)-1-6 (Feb. 2016).
DOI: 10.1103/PhysRevA.93.021606

"A New Numerical Method for Z2 Topological Insulators with Strong Disorder"
Yutaka Akagi, Hosho Katsura, and Tohru Koma,
Journal of the Physical Society of Japan 86, 123710-1-4 (Dec. 2017).
https://doi.org/10.7566/JPSJ.86.123710

"Learning Disordered Topological Phases by Statistical Recovery of Symmetry"
Nobuyuki Yoshioka, Yutaka Akagi, and Hosho Katsura,
Physical Review B 97, 205110-1-9 (May. 2018).
DOI: 10.1103/PhysRevB.97.205110

"Z2 Topological Invariant for Magnon Spin Hall Systems"
Hiroki Kondo, Yutaka Akagi, and Hosho Katsura,
Physical Review B 99, 041110(R)-1-6 (Jan. 2019).
DOI: 10.1103/PhysRevB.99.041110

"Transforming Generalized Ising Model into Boltzmann Machine"
Nobuyuki Yoshioka, Yutaka Akagi, and Hosho Katsura,
Physical Review E 99, 032113-1-11 (Mar. 2019).
DOI: 10.1103/PhysRevE.99.032113