878 citations · 4k across the 83 of their papers we have counts for
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Schwinger boson theory for Kitaev quantum spin liquids
Daiki Sasamoto, Joji Nasu
The Kitaev model is an exactly solvable model with a quantum spin liquid ground state. While this model was originally proposed as an spin model on a honeycomb lattice, ext…
Thermal Hall transport in Kitaev spin liquids
Tsuyoshi Okubo, Joji Nasu, Takahiro Misawa +1
We investigate the thermal Hall conductivity in the Kitaev model with additional interactions under a magnetic field, employing a finite-temperature tensor network method benchmark…
Spin Seebeck Effect as a Probe for Majorana Fermions in Kitaev Spin Liquids
Yasuyuki Kato, Joji Nasu, Masahiro Sato +3
Quantum entanglement in strongly correlated electron systems often leads to exotic elementary excitations. Quantum spin liquids (QSLs) provide a paradigmatic example, where the ele…
Effects of magnetic fields and orbital angular momentum on excitonic condensation in two-orbital Hubbard model
Ryota Koga, Joji Nasu
We investigate the magnetic-field effects on a two-orbital Hubbard model that describes multiple spin states. Cobalt oxides have been investigated as materials possessing spin-stat…
Flavor-wave theory with quasiparticle damping at finite temperatures: Application to chiral edge modes in the Kitaev model
Shinnosuke Koyama, Joji Nasu
We propose a theoretical framework to investigate elementary excitations at finite temperatures within a localized electron model that describes the interactions between multiple d…
Majorana-fermion origin of the planar thermal Hall effect in the Kitaev magnet -RuCl
K. Imamura, S. Suetsugu, Y. Mizukami +11
The field-induced quantum disordered state of layered honeycomb magnet -RuCl is a prime candidate for Kitaev spin liquids hosting Majorana fermions and non-Abelian anyons. R…
Field-driven spatiotemporal manipulation of Majorana zero modes in a Kitaev spin liquid
Chihiro Harada, Atsushi Ono, Joji Nasu
The Kitaev quantum spin liquid possesses two fractional quasiparticles, itinerant Majorana fermions and localized visons. It provides a promising platform for realizing a Majorana…
Interedge spin resonance in the Kitaev quantum spin liquid
Takahiro Misawa, Joji Nasu, Yukitoshi Motome
The Kitaev model offers a platform for quantum spin liquids (QSLs) with fractional excitations, itinerant Majorana fermions and localized fluxes. Since these fractional excitations…
Field-direction Dependence of Majorana-mediated Spin Transport
H. Taguchi, A. Koga, Y. Murakami +2
We study the field-direction dependence of the Majorana-mediated spin transport in the Kitaev clusters with zigzag and armchair edges, applying a static magnetic field to one of th…
Ground-state phase diagram of spin- Kitaev-Heisenberg models
Kiyu Fukui, Yasuyuki Kato, Joji Nasu +1
The Kitaev model, whose ground state is a quantum spin liquid (QSL), was originally conceived for spin moments on a honeycomb lattice. In recent years, the model has been e…
Scattering phenomena for spin transport in Kitaev spin liquid
Joji Nasu, Yuta Murakami, Akihisa Koga
The Kitaev model exhibits a canonical quantum spin liquid as a ground state and hosts two fractional quasiparticles, itinerant Majorana fermion and localized flux excitation. The f…
Feasibility of Kitaev quantum spin liquids in ultracold polar molecules
Kiyu Fukui, Yasuyuki Kato, Joji Nasu +1
Ultracold atoms and molecules trapped in optical lattices are expected to serve as simulators of strongly correlated systems and topological states of matter. A fascinating example…
Evidence for the first-order topological phase transition in a Kitaev spin liquid candidate -RuCl
S. Suetsugu, Y. Ukai, M. Shimomura +9
The Kitaev quantum spin liquid (QSL) on the two-dimensional honeycomb lattice epitomizes an entangled topological state, where the spins fractionalize into Majorana fermions. This…
Signature of spin-triplet exciton condensations in LaCoO at ultrahigh magnetic fields up to 600 T
Akihiko Ikeda, Yasuhiro H. Matsuda, Keisuke Sato +5
Bose-Einstein condensation of electron-hole pairs, exciton condensation, has been effortfully investigated since predicted 60 years ago. Irrefutable evidence has still been lacking…
Antisymmetric Thermopolarization by Electric Toroidicity
Joji Nasu, Satoru Hayami
We investigate electric polarizations emergent perpendicular to an applied thermal gradient in insulating systems. The thermally-induced electric polarization, known as thermopolar…
Role of Majorana fermions in spin transport of anisotropic Kitaev model
Hirokazu Taguchi, Yuta Murakami, Akihisa Koga +1
We study a quantum spin Kitaev model with zigzag edges to clarify the effects of anisotropy in the exchange couplings on the spin propagation. We simulate the spin and Majorana dyn…
Field-angle dependence of thermal Hall conductivity in magnetically ordered Kitaev-Heisenberg system
Shinnosuke Koyama, Joji Nasu
We study magnetic excitations and thermal Hall effect on the Kitaev-Heisenberg model under magnetic fields. By employing the spin-wave theory for the magnetic orders realized in th…
Spin dynamics in the Kitaev model with disorder: Quantum Monte Carlo study of dynamical spin structure factor, magnetic susceptibility, and NMR relaxation rate
Joji Nasu, Yukitoshi Motome
We investigate the impact of two types of disorder, bond randomness and site dilution, on the spin dynamics in the Kitaev model on a honeycomb lattice. The ground state of this mod…
Majorana correlations in the Kitaev model with ordered-flux structures
Akihisa Koga, Yuta Murakami, Joji Nasu
We study the effects of the flux configurations on the emergent Majorana fermions in the Kitaev model on a honeycomb lattice, where quantum spins are fractionalized into it…
Spin Seebeck Effect in Nonmagnetic Excitonic Insulators
Joji Nasu, Makoto Naka
We propose a mechanism of the spin Seebeck effect attributed to excitonic condensation in a nonmagnetic insulator. We analyze a half-filled two-orbital Hubbard model with a crystal…
Strong enhancement of magnetic susceptibility induced by spin-nematic fluctuations in an excitonic insulating system with spin-orbit coupling
Joji Nasu, Makoto Naka, Sumio Ishihara
Effects of the spin-orbit coupling (SOC) and magnetic field on excitonic insulating (EI) states are investigated. We introduce the two-orbital Hubbard model with the crystalline fi…
Thermodynamic and Transport Properties in Disordered Kitaev Models
Joji Nasu, Yukitoshi Motome
Effects of bond randomness and site dilution are systematically investigated for the Kitaev model describing a quantum spin liquid with fractional excitations of itinerant Majorana…
The range of non-Kitaev terms and fractional particles in RuCl
Yiping Wang, Gavin B. Osterhoudt, Yao Tian +12
Significant efforts have focused on the magnetic excitations of relativistic Mott insulators, predicted to realize the Kitaev quantum spin liquid (QSL). This exactly solvable model…
Spin transport in the Quantum Spin Liquid State in the Kitaev model: role of the fractionalized quasiparticles
Akihisa Koga, Tetsuya Minakawa, Yuta Murakami +1
We investigate the real-time spin response of the Kitaev model upon stimuli of a pulsed magnetic field in one of the edges using the exact diagonalization method. It is found…