RIKEN Center for Emergent Matter Science Computational Quantum Matter Research Team

Team Leader: Seiji Yunoki (D.Eng.)

Japanese Page

Research Summary

Materials exhibit a wide variety of properties including metal, semiconductor, magnetism, and superconductor. These different properties are caused by the different behavior of electrons inside materials. The main purpose of our research team is to microscopically understand a variety of quantum phenomena in solid materials using state-of-the-art numerical simulations. The electron in materials interacts with other electrons via Coulomb interaction, nuclei via electron-phonon interaction, and itself via spin-orbit interaction. We particularly focus on emergent quantum phenomena induced cooperatively by these interactions.

Main Research Fields

Mathematical & Physical Sciences

Related Research Fields

Interdisciplinary Science & Engineering

Keywords

Strongly correlated quantum systems
Transition metal oxides
Quantum dynamics

Selected Publications

1.B. H. Kim, T. Shirakawa, and S. Yunoki,
"From a quasimolecular band insulator to a relativistic Mott insulator in t_2g⁵ systems with a honeycomb lattice structure",
Physical Review Letters 117, 187201/1-6 (2016).
2.Q. Cui, J.-G. Cheng, W. Fan, A. E. Taylor, S. Calder, M. A. McGuire, J.-Q. Yan, D. Meyers, X. Li, Y. Q. Cai, Y. Y. Jiao, Y. Choi, D. Haskel, H. Gotou, Y. Uwatoko, J. Chakhalian, A. D. Christianson, S. Yunoki, J. B. Goodenough, and J.-S. Zhou,
"Slater insulator in iridate perovskites with strong spin-orbit coupling",
Physical Review Letters 117, 176603/1-6 (2016).
3.T. Shirakawa and S. Yunoki,
"Density matrix renormalization group study in energy space for a single-impurity Anderson model and an impurity quantum phase transition",
Physical Review B 93, 205124/1-17 (2016).
4.H. Watanabe, K. Seki, and S. Yunoki,
"Charge-density wave induced by combined electron-electron and electron-phonon interactions in 1T−TiSe₂: A variational Monte Carlo study",
Physical Review B 91, 205135/1-6 (2015).
5.T. Sato, T. Shirakawa, and S. Yunoki,
"Spin-orbit-induced exotic insulators in a three-orbital Hubbard model with (t_2g)⁵ electrons",
Physical Review B 91, 125122/1-5 (2015).
6.T. Shirakawa and S. Yunoki,
"Block Lanczos density-matrix renormalization group method for general Anderson impurity models: Application to magnetic impurity problems in graphene",
Physical Review B 90, 195109/1-21 (2014).
7.H. Watanabe, T. Shirakawa, and S. Yunoki,
"Theoretical study of insulating mechanism in multiorbital Hubbard models with a large spin-orbit coupling: Slater vs. Mott scenario in Sr₂IrO₄",
Physical Review B 89, 165115/1-13 (2014).
8.H. Watanabe, T. Shirakawa, and S. Yunoki,
"Monte Carlo study of an unconventional superconducting phase in Iridium oxide J_eff = 1/2 Mott insulators induced by carrier doping",
Physical Review Letters 110, 027002/1-5 (2013).
9.A. Annadi, Q. Zhang, X. Renshaw Wang, N. Tuzla, K. Gopinadhan, W. M. Lu, A. Roy Barman, Z. Q. Liu, A. Srivastava, S. Saha, Y. L. Zhao, S. W. Zeng, S. Dhar, E. Olsson, B. Gu, S. Yunoki, S. Maekawa, H. Hilgenkamp, T. Venkatesan, and A. Ariando,
"Anisotropic two-dimensional electron gas at the LaAlO₃/SrTiO₃ (110) interface",
Nature Communications 4, 1838/1-7 (2013).

Recent Research Results

Jul. 14, 2021
Two-dimensional materials and interfaces can convert spin current into a vortex of charge current
May 31, 2013
Iridium’s new lustre
May 2, 2013
In or out of phase?

Lab Members

Principal investigator

Seiji Yunoki: Team Leader

Core members

Kazuya Shinjo: Research Scientist

Careers

Position	Deadline
Seeking a Postdoctoral Researcher (W23171)	Open until filled

Contact Information

2-1 Hirosawa, Wako, Saitama 351-0198, Japan
Email: yunoki [at] riken.jp