22 citations · 50 across the 18 of their papers we have counts for
12 papers · 1 filter
Chiral Antiferromagnetism from Momentum-Space Resonance in a 2D Semiconductor
R. Okuma, T. Ikenobe, Y. Fujisawa +28
Understanding the principles governing the emergence of chiral quantum phases is a fundamental challenge, not only for uncovering new mechanisms of quantum-state formation but also…
Field-tuned incommensurate fan phase in an Ising-like triangular antiferromagnet
D. Flavián, R. Okuma, P. Manuel +3
Using single-crystal neutron diffraction we report the observation of a field-tuned incommensurate phase in a field range just below magnetization saturation in the Ising-like tria…
Stabilizing Itinerant Electrons in a Corner-Sharing Kagomé Oxide Nd4Os3ZnO14
Ryutaro Okuma, Yuita Fujisawa, Chia-Hsiu Hsu +8
Kagome oxides provide a fertile platform for exploring exotic electronic states arising from geometrical frustration and characteristic band topology. Here, we report the synthesis…
Molecular-Orbital Degeneracy Lifting and Suppression of a Flat-Band Metal in a Tetrahedral Cluster System NbSeI
Keita Kojima, Youichi Yamakawa, Ryutaro Okuma +7
The lifting of degenerate electronic states has been extensively studied in transition metal compounds, where diverse quantum phenomena arise from the degrees of freedom of d elect…
From continuum excitations to sharp magnons via transverse magnetic field in the spin-1/2 Ising-like triangular lattice antiferromagnet Na2BaCo(PO4)2
Leonie Woodland, Ryutaro Okuma, J. Ross Stewart +2
We report high-resolution inelastic neutron scattering measurements of the excitation spectrum in large single crystals of the spin-1/2 triangular lattice Ising-like antiferromagne…
Uncovering hidden Fermi surface instabilities through visualizing unconventional quasiparticle interference in CeTe3
B. R. M. Smith, Y. Fujisawa, P. Wu +14
The charge density wave (CDW) state is a widespread phenomenon in low-dimensional metals/semimetals. The spectral weight of the associated folded bands (shadow bands) can be an int…
Selective synthesis and crystal chemistry of candidate rare earth Kitaev materials: honeycomb and hyperhoneycomb NaPrO
Ryutaro Okuma, Kylie MacFarquharson, Radu Coldea
Rare earth oxides have attracted interest as a platform for studying frustrated magnetism arising from bond dependent anisotropic interactions. Ordered rock salt compounds NaPr…
Compass-model physics on the hyperhoneycomb lattice in the extreme spin-orbit regime
Ryutaro Okuma, Kylie MacFarquharson, Roger D. Johnson +3
The physics of spin-orbit entangled magnetic moments of and transition metal ions on a honeycomb lattice has been much explored in search for unconventional magnetic orde…
Emergent topological magnetism in Hund's excitonic insulator
R. Okuma, K. Yamagami, Y. Fujisawa +14
Analogous to the charged electron-electron pair condensation in superconductors, an excitonic insulator (EI) represents Fermi surface instability due to spontaneous formation and c…
Negative-chirality order in kagome antiferromagnet CdCu(OH)(NO)HO
Yoshihiko Ihara, Ryoga Hiyoshi, Masakazu Shimohasi +4
The neutron diffraction and nuclear magnetic resonance (NMR) measurements have been used to microscopically analyze the magnetic structure in the kagome antiferromagnet C…
Magnetic frustration in a van der Waals metal CeSiI
Ryutaro Okuma, Clemens Ritter, Gøran J. Nilsen +1
The realization of magnetic frustration in a metallic van der Waals (vdW) coupled material has been sought as a promising platform to explore novel phenomena both in bulk matter an…
Phase diagram of multiferroic KCuAsO(OD)
Gøran J. Nilsen, Virginie Simonet, Claire V. Colin +6
The layered compound KCuAsO(OD), comprising distorted kagome planes of Cu ions, is a recent addition to the family of type-II multiferroics. Previous…