Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:cond-mat/0110284 · Physical review. B, Condensed matter

Dynamical structure factors of the magnetization plateau state in the S=12 bond-alternating spin chain with a next-nearest-neighbor interaction

Nobuyasu Haga, Sei-ichiro Suga

Published Nov 30, 2001• 12 citations
arXivHTMLPDF

Abstract

We calculate the dynamical structure factors of the magnetization plateau state in the $S=\frac{1}{2}$ bond-alternating spin chain with a next-nearest-neighbor interaction. The results show characteristic behaviors depending on the next-nearest-neighbor interaction $\ensuremath{\alpha}$ and the bond alternation \ensuremath{\delta}. We discuss the lower excited states in comparison with the exact excitation spectrums of an effective Hamiltonian. From the finite size effects, characteristics of the lowest excited states are investigated. The dispersionless mode of the lowest excitation appears in adequate sets of $\ensuremath{\alpha}$ and \ensuremath{\delta}, indicating that the lowest excitation is localized spatially and forms an isolated mode below the excitation continuum. We further calculate the static structure factors. The largest intensity is located at $q=\ensuremath{\pi}$ for small $\ensuremath{\delta}$ in fixed \ensuremath{\alpha}. With increasing \ensuremath{\delta}, the wave number of the largest intensity shifts towards $q=\ensuremath{\pi}/2,$ taking the incommensurate value.

DOI
10.1103/physrevb.65.014414

Related papers

Dynamics and Incommensurate Spin Correlation of the Magnetization Plateau State in theS=1/2 Bond-Alternating Spin Chain with a Next-Nearest-Neighbor Interaction

Sei-ichiro Suga, Nobuyasu Haga

We investigate dynamical properties of the magnetization plateau state in the S=1/2 bond-alternating spin chain with a next-nearest-neighbor interaction. The dynamical structure factor shows characteristic behavior depending on the next-nearest-neighbor interaction α and the bond alternation δ. The static structure factor takes the largest value at q=π for small δ. With increasing δ, the wave number of the largest value shifts towards q=π/2, taking the incommensurate value.

Progress of Theoretical Physics Supplement•Jan 1, 2002•0 citations

DYNAMICAL PROPERTIES OF FIELD-INDUCED ORDERED-STATES IN S = 1/2 ONE-DIMENSIONAL QUANTUM SPIN SYSTEMS

Nobuyasu Haga, Sei-ichiro Suga

We calculate the dynamical structure factors of the magnetization-plateau state in the S = 1/2 bond-alternating spin chain with a next-nearest-neighbor interaction. The results show characteristic behaviors depending on the next-nearest-neighbor interaction and the bond-alternation. We discuss the lower excited states in comparison with the exact excitation spectrums of an effective Hamiltonian.

International Journal of Modern Physics B•Aug 30, 2002•0 citations

Dynamical Structure Factors of theS=1/2Bond-Alternating Spin Chain with a Next-Nearest-Neighbor Interaction in Magnetic Fields

Mamoru Usami, Sei-ichiro Suga

The dynamical structure factor of the S=1/2 bond-alternating spin chain with a next-nearest-neighbor interaction in magnetic field is investigated using the continued fraction method based on the Lanczos algorithm. When the plateau exists on the magnetization curve, the longitudinal dynamical structure factor shows a large intensity with a periodic dispersion relation, while the transverse one shows a large intensity with an almost dispersionless mode. The periodicity and the amplitude of the dispersion relation in the longitudinal dynamical structure factor are sensitive to the coupling constants. The dynamical structure factor of the S=1/2 two-leg ladder in magnetic field is also calculated in the strong interchain-coupling regime. The dynamical structure factor shows gapless or gapful behavior depending on the wave vector along the rung.

arXiv:cond-mat/0007219•Journal of the Physical Society of Japan•Oct 15, 2000•1 citation

DYNAMICAL STRUCTURE FACTORS OF THE S = 1/2 SPIN LADDER SYSTEMS WITH A DIAGONAL INTERACTION IN THE MAGNETIZATION-PLATEAU STATE

Nobuyasu Haga, Sei-ichiro Suga

We investigate the dynamical structure factors of the S = 1/2 spin ladder systems with a diagonal interaction in the magnetization-plateau state. The results show characteristic behaviors depending on the chain interaction α, the ladder interaction 1 + δ and the diagonal interaction 1 - δ. The large weights are located at q = π, when δ is small. With increasing δ, the wavenumber of the large weights shifts towards q = π/2 taking the incommensurate value. The almost dispersionless behavior comes out at several combinations of α and δ, indicating that the elementary excitation is localized spatially. We discuss our results in comparison with the exact excitation spectrums of the S = 1/2 XXZ model which is an effective Hamiltonian of the present system in α ~ 0 and δ ~ 1. Dynamical structure factors of some S = 1/2 one-dimensional quantum spin systems in the magnetic fields were measured by inelastic neutron-scattering experiments1,2 and it has been shown the theoretical results from the numerical diagonalization of finite systems can explain them.3–5

International Journal of Modern Physics B•Aug 30, 2002•0 citations

Spin dynamics of the half-magnetization plateau in S = 1 bond-alternating spin chains

T. Suzuki, Sei-ichiro Suga

We investigate dynamical properties of the half-magnetization plateau in S = 1 bond-alternating spin chains. Dynamical structure factors calculated by the exact diagonalization method are compared with the dispersion curves of low-lying excitations obtained by a cluster expansion technique. We find that in the half-magnetization plateau the quintet excitation forms the lowest-lying excitation. The field dependence of the critical exponents of the spin correlation functions are further investigated. On the basis of the results, characteristics of the half-magnetization plateau are discussed.

Journal of Physics Conference Series•Nov 1, 2006•0 citations

Dynamical structure factors of S=1 bond-alternating Heisenberg chains

Takahumi Suzuki, Sei-ichiro Suga

We calculate the dynamical structural factor of the $S=1$ bond-alternating Heisenberg chain. In the Haldane phase, the lowest excited states form the lower edge of the multimagnon continuum in $0<~q<~{q}_{c}$ and the one-magnon mode in ${q}_{c}<~q<~\ensuremath{\pi}.$ As the system approaches the gapless point, ${q}_{c}$ shifts towards $q=\ensuremath{\pi}$ and the largest integrated intensity of the one-magnon mode is decreased. In the singlet-dimer phase, the one-magnon mode appears in $0<~q<~{q}_{c}.$ As the bond-alternation becomes strong, ${q}_{c}$ shifts towards $q=\ensuremath{\pi}.$ In the antiferromagnetic-ferromagnetic bond-alternation region with a strong ferromagnetic coupling, the lowest excited states form the lower edge of the multimagnon continuum in $0<~q<~0.2\ensuremath{\pi}$ and $0.8\ensuremath{\pi}<~q<~\ensuremath{\pi},$ and the one-magnon mode appears in $0.2\ensuremath{\pi}<q<0.8\ensuremath{\pi}.$ The largest integrated intensity of the one-magnon mode is $93%,$ which is slightly smaller than that in the $S=1$ Haldane-gap system. We further discuss the dynamical structural factor in connection with the inelastic neutron-scattering experiments.

arXiv:cond-mat/0309178•Physical review. B, Condensed matter•Oct 17, 2003•5 citations
We calculate the dynamical structure factors of the magnetization plateau state in the S=12S=\frac{1}{2}S=21​ bond-alternating spin chain with a next-nearest-neighbor interaction. The results show characteristic behaviors depending on the next-nearest-neighbor interaction \ensuremathα\ensuremath{\alpha}\ensuremathα and the bond alternation \ensuremath{\delta}. We discuss the lower excited states in comparison with the exact excitation spectrums of an effective Hamiltonian. From the finite size effects, characteristics of the lowest excited states are investigated. The dispersionless mode of the lowest excitation appears in adequate sets of \ensuremathα\ensuremath{\alpha}\ensuremathα and \ensuremath{\delta}, indicating that the lowest excitation is localized spatially and forms an isolated mode below the excitation continuum. We further calculate the static structure factors. The largest intensity is located at q=\ensuremathπq=\ensuremath{\pi}q=\ensuremathπ for small \ensuremathδ\ensuremath{\delta}\ensuremathδ in fixed \ensuremath{\alpha}. With increasing \ensuremath{\delta}, the wave number of the largest intensity shifts towards q=\ensuremathπ/2,q=\ensuremath{\pi}/2,q=\ensuremathπ/2, taking the incommensurate value.
The dynamical structure factor of the S=1/2 bond-alternating spin chain with a next-nearest-neighbor interaction in magnetic field is investigated using the continued fraction method based on the Lanczos algorithm. When the plateau exists on the magnetization curve, the longitudinal dynamical structure factor shows a large intensity with a periodic dispersion relation, while the transverse one shows a large intensity with an almost dispersionless mode. The periodicity and the amplitude of the dispersion relation in the longitudinal dynamical structure factor are sensitive to the coupling constants. The dynamical structure factor of the S=1/2 two-leg ladder in magnetic field is also calculated in the strong interchain-coupling regime. The dynamical structure factor shows gapless or gapful behavior depending on the wave vector along the rung.
We investigate the dynamical structure factors of the S = 1/2 spin ladder systems with a diagonal interaction in the magnetization-plateau state. The results show characteristic behaviors depending on the chain interaction α, the ladder interaction 1 + δ and the diagonal interaction 1 - δ. The large weights are located at q = π, when δ is small. With increasing δ, the wavenumber of the large weights shifts towards q = π/2 taking the incommensurate value. The almost dispersionless behavior comes out at several combinations of α and δ, indicating that the elementary excitation is localized spatially. We discuss our results in comparison with the exact excitation spectrums of the S = 1/2 XXZ model which is an effective Hamiltonian of the present system in α ~ 0 and δ ~ 1. Dynamical structure factors of some S = 1/2 one-dimensional quantum spin systems in the magnetic fields were measured by inelastic neutron-scattering experiments1,2 and it has been shown the theoretical results from the numerical diagonalization of finite systems can explain them.3–5
We investigate dynamical properties of the half-magnetization plateau in S = 1 bond-alternating spin chains. Dynamical structure factors calculated by the exact diagonalization method are compared with the dispersion curves of low-lying excitations obtained by a cluster expansion technique. We find that in the half-magnetization plateau the quintet excitation forms the lowest-lying excitation. The field dependence of the critical exponents of the spin correlation functions are further investigated. On the basis of the results, characteristics of the half-magnetization plateau are discussed.
We calculate the dynamical structural factor of the S=1S=1S=1 bond-alternating Heisenberg chain. In the Haldane phase, the lowest excited states form the lower edge of the multimagnon continuum in 0< q< qc0<~q<~{q}_{c}0< q< qc​ and the one-magnon mode in ${q}_{c}<~q<~\ensuremath{\pi}.$ As the system approaches the gapless point, qc{q}_{c}qc​ shifts towards $q=\ensuremath{\pi}$ and the largest integrated intensity of the one-magnon mode is decreased. In the singlet-dimer phase, the one-magnon mode appears in 0< q< qc.0<~q<~{q}_{c}.0< q< qc​. As the bond-alternation becomes strong, qc{q}_{c}qc​ shifts towards $q=\ensuremath{\pi}.$ In the antiferromagnetic-ferromagnetic bond-alternation region with a strong ferromagnetic coupling, the lowest excited states form the lower edge of the multimagnon continuum in $0<~q<~0.2\ensuremath{\pi}$ and $0.8\ensuremath{\pi}<~q<~\ensuremath{\pi},$ and the one-magnon mode appears in $0.2\ensuremath{\pi}<q<0.8\ensuremath{\pi}.$ The largest integrated intensity of the one-magnon mode is 9393%,93 which is slightly smaller than that in the S=1S=1S=1 Haldane-gap system. We further discuss the dynamical structural factor in connection with the inelastic neutron-scattering experiments.