104 citations · 794 across the 40 of their papers we have counts for
12 papers · 1 filter
Nematic Tomonaga-Luttinger Liquid Phase in an Ferromagnetic-Antiferromagnetic Bond-Alternating Chain
Takashi Tonegawa, Kiyomi Okamoto, Kiyohide Nomura +1
We numerically investigate the ground-state phase diagram of the ferromagnetic-antiferromagnetic bond-alternating chain, in which the ferromagnetic interactions are stronge…
Haldane, Large-D and Intermediate-D States in an S=2 Quantum Spin Chain with On-Site and XXZ Anisotropies
Takashi Tonegawa, Kiyomi Okamoto, Hiroki Nakano +3
Using mainly numerical methods, we investigate the ground-state phase diagram of the S=2 quantum spin chain described by $H = \sum_j (S_j^x S_{j+1}^x + S_j^y S_{j+1}^y + ΔS_j^z S_{…
Cancellation of oscillatory behaviors in incommensurate region
Takahiro Murashima, Kiyohide Nomura
In several frustrating systems incommensurate behaviors are often observed. For the S=1 bilinear-biquadratic model, we show that the main oscillatory behavior, which is proportiona…
Incommensurability and edge states in the one-dimensional S=1 bilinear-biquadratic model
Takahiro Murashima, Kiyohide Nomura
Commensurate-incommensurate change on the one-dimensional S=1 bilinear-biquadratic model () i…
Phase diagram of S=1/2 two-leg XXZ spin ladder systems
K. Hijii, A. Kitazawa, K. Nomura
We investigate the ground state phase diagram of the S=1/2 two-leg spin ladder system with an isotropic interchain coupling. In this model, there is the Berezinskii-Kosterlit…
Phase diagram of S=1 XXZ chain with next-nearest neighbor interaction
Takahiro Murashima, Keigo Hijii, Kiyohide Nomura +1
The one dimensional S=1 XXZ model with next-nearest-neighbor interaction and Ising-type anisotropy is studied by using a numerical diagonalization technique. We discuss the…
Onset of incommensurability in quantum spin chains
Kiyohide Nomura
In quantum spin chains, it has been observed that the incommensurability occurs near valence-bond-solid (VBS)-type solvable points, and the correlation length becomes shortest at V…
BKT transition and level spectroscopy
Kiyohide Nomura, Atsuhiro Kitazawa
Berezinskii-Kosterlitz-Thouless (BKT) transition is one of the instability mechanisms for the Tomonaga-Luttinger liquid. But in the BKT transition, there are logarithmic-correction…
Spin-Gap Phases in Tomonaga-Luttinger Liquids
Masaaki Nakamura, Atsuhiro Kitazawa, Kiyohide Nomura
We give the details of the analysis for critical properties of spin-gap phases in one-dimensional lattice electron models. In the Tomonaga-Luttinger (TL) liquid theory, the spin-ga…
Renormalization group analysis of the spin-gap phase in the one-dimensional t-J model
Masaaki Nakamura, Kiyohide Nomura, Atsuhiro Kitazawa
We study the spin-gap phase in the one-dimensional t-J model, assuming that it is caused by the backward scattering process. Based on the renormalization group analysis and symmetr…
Phase Diagram of S=1 Bond-Alternating XXZ Chains Reflecting the Hidden Z_2\times Z_2 Symmetry
Atsuhiro Kitazawa, Kiyohide Nomura
The phase diagram of the spin-1 bond-alternating XXZ chain is studied numerically. This model is appropriate to study the VBS picture and the hidden Z_2\times Z_2 symmetry concerni…
Phase separation as an instability of the Tomonaga-Luttinger liquid
Masaaki Nakamura, Kiyohide Nomura
Asymptotic behavior of the Tomonaga-Luttinger liquid in the vicinity of the phase-separated region is investigated in the one-dimensional - model, to study the universal prop…