99 citations · 209 across the 8 of their papers we have counts for
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Long-Range Order of the Three-Sublattice Structure in the S = 1 Heisenberg Antiferromagnet on a Spatially Anisotropic Triangular Lattice
Hiroki Nakano, Synge Todo, Toru Sakai
We study the S=1 Heisenberg antiferromagnet on a spatially anisotropic triangular lattice by the numerical diagonalization method. We examine the stability of the long-range order…
Path-integral Monte Carlo method for the local Z_2 Berry phase
Yuichi Motoyama, Synge Todo
We present a loop cluster algorithm Monte Carlo method for calculating the local Z_2 Berry phase of the quantum spin models. The Berry connection, which is given as the inner produ…
Improved chain mean-field theory for quasi-one-dimensional quantum magnets
Synge Todo, Akira Shibasaki
A novel mean-field approximation for quasi-one-dimensional (Q1D) quantum magnets is formulated. Our new mean-field approach is based on the Bethe-type effective-field theory, where…
Green's function theory for spin-1/2 ferromagnets with an easy-plane exchange anisotropy
Daisuke Yamamoto, Synge Todo, Susumu Kurihara
The many-body Green's function theory with the random-phase approximation is applied to the study of easy-plane spin-1/2 ferromagnets in an in-plane magnetic field. We demonstrate…
Parity law of the singlet-triplet gap in graphitic ribbons
Mohamad Al Hajj, Fabien Alet, Sylvain Capponi +3
This work explores the possibility to transfer the parity law of the singlet-triplet gap established for square ladders (gapped for even number of legs, gapless for odd number of l…
Quantum phase transitions of spin chiral nanotubes
Munehisa Matsumoto, Toru Sakai, Masahiro Sato +2
Recently many interesting magnetic nanostructures have been fabricated and much attention is arising on the rich magnetic properties that originate in the quantum effects eminent i…