122 citations · 1.5k across the 70 of their papers we have counts for
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Spin-Wave Description of Haldane-gap antiferromagnets
Shoji Yamamoto, Hiromitsu Hori
Modifying the conventional antiferromagnetic spin-wave theory which is plagued by the difficulty of the zero-field sublattice magnetizations diverging in one dimension, we describe…
Spin-Wave Description of Nuclear Spin-Lattice Relaxation in Mn_{12}O_{12} Acetate
Shoji Yamamoto, Takashi Nakanishi
In response to recent nuclear-magnetic-resonance (NMR) measurements on the molecular cluster Mn_{12}O_{12} acetate, we study the nuclear spin-lattice relaxation rate 1/T_1 developi…
Local excitations in mixed-valence bimetal chains
Shoji Yamamoto
We investigate localized intragap states in mixed-valence bimetal chains in an attempt to encourage further explorations into quasi-one-dimensional halogen-bridged binuclear metal…
Quantum and thermal phase transitions in the Bechgaard salts and their analogs
Hiromitsu Hori, Shoji Yamamoto
In order to investigate quantum and thermal phase transitions in the Bechgaard salts and their sulfur analogs, we perform finite-temperature Hartree-Fock calculations in one dimens…
Intrinsic double-peak structure of the specific heat in low-dimensional quantum ferrimagnets
Takashi Nakanishi, Shoji Yamamoto
Motivated by recent magnetic measurements on A3Cu3(PO4)4 (A=Ca,Sr) and Cu(3-Clpy)2(N3)2 (3-Clpy=3-Chloropyridine), both of which behave like one-dimensional ferrimagnets, we extens…
Fermionic description of spin-gap states of antiferromagnetic Heisenberg ladders in a magnetic field
Hiromitsu Hori, Shoji Yamamoto
Employing the Jordan-Wigner transformation on a unique path and then making a mean-field treatment of the fermionic Hamiltonian, we semiquantitatively describe the spin-gap states…
Re-Entrant Quantum Phase Transitions in Antiferromagnetic Spin-1 Ladders
Shoji Yamamoto, Toru Sakai, Akihisa Koga
In response to recent chemical attempts to construct higher-spin ladder materials from organic polyradicals, we study the ground-state properties of a wide class of antiferromagnet…