23 citations · 55 across the 7 of their papers we have counts for
8 papers
Chiral Valence-Bond Solid and Chiral Triplons
Shinnosuke Koyama, Kazumasa Hattori
We propose a chiral valence-bond solid (VBS) in which spin-singlet bond order itself spontaneously acquires handedness without magnetic order. Using a spin-lattice model on the dia…
Halogen control of magnetic competition in Kitaev candidate Ru ( Cl, Br)
Ryuta Iwazaki, Shinnosuke Koyama, Takashi Koretsune +2
The spin-orbital Mott insulators Ru ( Cl, Br) have attracted considerable attention as promising candidate materials for realizing a Kitaev spin liquid. In this study, we…
Flexocurrent-induced magnetization: Strain gradient-induced magnetization in time-reversal symmetric systems
Shinnosuke Koyama, Takashi Koretsune, Kazumasa Hattori
Symmetry constraints determine which physical responses are allowed in a given system. Magnetization induced by strain fields, such as in piezomagnetic and flexomagnetic effects, h…
Formulation of spin Nernst effect for spin-nonconserving insulating magnets
Shinnosuke Koyama, Joji Nasu
The spin Nernst effect, an antisymmetric response of a spin current to a temperature gradient, has attracted attention as spin transport phenomenon arising from the topologically n…
Impact of triplon damping on thermal Hall conductivity in Shastry-Sutherland model
Shinnosuke Koyama, Joji Nasu
We investigate the thermal Hall effect in the Shastry-Sutherland model, incorporating interactions between quasiparticle excitations. In this model, with strong nearest-neighbor in…
Thermal Hall effect incorporating magnon damping in localized spin systems
Shinnosuke Koyama, Joji Nasu
We propose a theory for thermal Hall transport mediated by magnons to address the impact of their damping resulting from magnon-magnon interactions in insulating magnets. This phen…
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…
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…