159 citations · 815 across the 33 of their papers we have counts for
24 papers · 1 filter
Supersymmetry Breaking in a Generalized Nicolai Model with Fermion Pairing
Urei Miura, Keisuke Totsuka
We introduce a supersymmetric lattice fermion model that contains both fermion pairing and the interacting Nicolai model. This model possesses a single control parameter, , intr…
Ferromagnetism in the SU(N) Kondo lattice model -- SU(N) double exchange and supersymmetry
Keisuke Totsuka
We study the ground-state properties of the SU(N)-generalization of the Kondo-lattice model in one dimension when the Kondo coupling J_K (both ferromagnetic and antiferromagnetic)…
Electric and Magnetic Properties of Higher-Spin Kondo-Heisenberg Models at Strong Coupling
Riku Masui, Keisuke Totsuka
We study higher-spin () generalization of the one-dimensional Kondo-Heisenberg model, in which the local spin- moments of the Kondo lattice model interact with each ot…
Intrinsic suppression of topological thermal Hall effect in an exactly solvable quantum magnet
S. Suetsugu, T. Yokoi, K. Totsuka +7
In contrast to electron (fermion) systems, topological phases of charge neutral bosons have been poorly understood despite recent extensive research on insulating magnets. The most…
Abelian SU Chiral Spin Liquids on the Square Lattice
Ji-Yao Chen, Jheng-Wei Li, Pierre Nataf +7
In the physics of the Fractional Quantum Hall (FQH) effect, a zoo of Abelian topological phases can be obtained by varying the magnetic field. Aiming to reach the same phenomenolog…
From coupled-wire construction of quantum Hall states to wave functions and hydrodynamics
Y. Imamura, K. Totsuka, T. H. Hansson
In this paper we use a close connection between the coupled wire construction (CWC) of Abelian quantum Hall states and the theory of composite bosons to extract the Laughlin wave f…
"Haldane" phases with ultracold fermionic atoms in double-well optical lattices
P. Fromholz, S. Capponi, P. Lecheminant +2
We propose to realize one-dimensional topological phases protected by SU() symmetry using alkali or alkaline-earth atoms loaded into a bichromatic optical lattice. We derive a r…
Bulk effective theory in coupled wire construction from generalized Wilson line
Yukihisa Imamura, Keisuke Totsuka
We reconsider the coupled wire construction, which is a useful method of obtaining two and three-dimensional topologically ordered states from an array of one-dimensional CFTs, and…
Density-Matrix Renormalization Group Study of Kitaev--Heisenberg Model on a Triangular Lattice
Kazuya Shinjo, Shigetoshi Sota, Seiji Yunoki +2
We study the Kitaev--Heisenberg model on a triangular lattice by using the two-dimensional density-matrix renormalization group method. Calculating the ground-state energy and spin…
Symmetry-protected topological order in SU(N) Heisenberg magnets --quantum entanglement and non-local order parameters
K. Tanimoto, K. Totsuka
In this paper, we investigate topological properties of the ground state of the SU(N) Heisenberg chain, which is argued to be relevant to the Mott-insulating phase of alkaline-eart…
Magnetization plateaus of an easy-axis Kagomé antiferromagnet with extended interactions
X. Plat, F. Alet, S. Capponi +1
We investigate the properties in finite magnetic field of an extended anisotropic XXZ spin-1/2 model on the Kagome lattice, originally introduced by Balents, Fisher, and Girvin [Ph…
Symmetry-protected topological order in magnetization plateau states of quantum spin chains
Shintaro Takayoshi, Keisuke Totsuka, Akihiro Tanaka
A symmetry-protected topologically ordered phase is a short-range entangled state, for which some imposed symmetry prohibits the adiabatic deformation into a trivial state which la…
Stability and magnetization curve of spin-nematic phase slightly below saturation field
Hiroaki T. Ueda, Keisuke Totsuka
We discuss the magnetization process slightly below the saturation field in frustrated magnets. A condensation of bound magnons on the spin-polarized state induces either a spin ne…
Quantum Entanglement and Topological Order in Hole-Doped Valence Bond Solid States
Kazuki Hasebe, Keisuke Totsuka
We present a detailed analysis of topological properties of the valence bond solid (VBS) states doped with fermionic holes. As concrete examples, we consider the supersymmetric ext…
Hidden Order and Dynamics in Supersymmetric Valence Bond Solid States -- Super-Matrix Product State Formalism
Kazuki Hasebe, Keisuke Totsuka
Supersymmetric valence bond solid models are extensions of the VBS model, a paradigmatic model of `solvable' gapped quantum antiferromagnets, to the case with doped fermionic holes…
Extended Quantum Dimer Model and novel valence-bond phases
Kouki Nakata, Keisuke Totsuka
We extend the quantum dimer model (QDM) introduced by Rokhsar and Kivelson so as to construct a concrete example of the model which exhibits the first-order phase transition betwee…
The effect of Dzyaloshinskii-Moriya interactions on the phase diagram and magnetic excitations of SrCu2(BO3)2
Judit Romhanyi, Keisuke Totsuka, Karlo Penc
The orthogonal dimer structure in the SrCu2(BO3)2 spin-1/2 magnet provides a realization of the Shastry-Sutherland model. Using a dimer-product variational wave function, we map ou…
Dimer Smectic in Extended Quantum Dimer Model -approach from pseudo S=1 Hamiltonian-
Kouki Nakata, Keisuke Totsuka
We extend Quantum Dimer Model (QDM) introduced by Rokhsar and Kivelson in such a way that the model includes resonance processes on larger loops. The strategy is to first construct…
Ground-state phase diagram and magnetic properties of a tetramerized spin-1/2 J_1-J_2 model: BEC of bound magnons and absence of the transverse magnetization
H. T. Ueda, K. Totsuka
We study the ground state and the magnetization process of a spin-1/2 - model with a plaquette structure by using various methods. For small inter-plaquette interaction,…
Spontaneous trimerization in a bilinear-biquadratic S=1 zig-zag chain
Philippe Corboz, Andreas M. Laeuchli, Keisuke Totsuka +1
Recent theoretical studies raised the possibility of a realization of spin nematic states in the S=1 triangular lattice compound NiGa_2S_4. We study the bilinear-biquadratic spin 1…
Competing Orders and Hidden Duality Symmetries in Two-leg Spin Ladder Systems
P. Lecheminant, K. Totsuka
A unifying approach to competing quantum orders in generalized two-leg spin ladders is presented. Hidden relationship and quantum phase transitions among the competing orders are t…
Phases of the generalized two-leg spin ladder: A view from the SU(4) symmetry
P. Lecheminant, K. Totsuka
The zero-temperature phases of a generalized two-leg spin ladder with four-spin exchanges are discussed by means of a low-energy field theory approach starting from an SU(4) quantu…
Field-Induced gap due to four-spin exchange in a spin ladder
Atsushi Nakasu, Keisuke Totsuka, Yasumasa Hasegawa +2
The effect of the four-spin cyclic exchange interaction at each plaquette in the two-leg spin ladder is investigated at T=0, especially focusing on the field-induced gap. T…
Magnetization plateaus of the Shastry-Sutherland model for SrCu_2(BO_3)_2: SDW, supersolid and bound states
Tsutomu Momoi, Keisuke Totsuka
We study the Heisenberg antiferromagnet on the Shastry-Sutherland lattice under magnetic fields, to clarify the magnetic properties of SrCu_2(BO_3)_2. Treating magnetic excitations…