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

Physical Review Letters

Dominance of long-lived excitations in the antiferromagnetic spin-1 chain NENP

Shaolong Ma, C. Broholm, Daniel H. Reich, Benjamin Joel Sternlieb, Ross W. Erwin

Published Dec 14, 1992• 169 citations
Publisher

Abstract

We have measured the dynamic spin correlation function for the quasi-one-dimensional S=1 antiferromagnet NENP by inelastic magnetic neutron scattering. Long-lived excitations (\ensuremath{\omega}\ensuremath{\tau}>10) exist for 0.3\ensuremath{\pi}\ensuremath{\le}q\ifmmode \tilde{}\else \~{}\fi{}\ensuremath{\le}\ensuremath{\pi}, and within error exhuast the total moment sum rule. The dispersion relation retains the fundamental periodicity of the spin chain, explicitly demonstrating the absence of broken translational symmetry in the ground state. The instantaneous spin correlation function follows a square-root Lorentzian for q\ifmmode \tilde{}\else \~{}\fi{}\ensuremath{\simeq}\ensuremath{\pi} but deviates substantially from this form for q\ifmmode \tilde{}\else \~{}\fi{}0.8\ensuremath{\pi}.

DOI
10.1103/physrevlett.69.3571

Related papers

Dynamical properties of a Haldane-gap antiferromagnet

O. Golinelli, Th. Jolicœur, R. Lacaze

The authors study the dynamic spin correlation function of a spin-1 antiferromagnetic chain with easy-plane single-ion anisotropy. They use exact diagonalization by the Lanczos method for chains of length up to N=16 spins. They show that a single-mode approximation is an excellent description of the dynamical properties. A variational calculation allows them to clarify the nature of the excitations. The existence of a two-particle continuum near-zero wavevector is clearly seen, both in finite-size effects and in the dynamical structure factor. The recent neutron scattering experiments on the quasi-one-dimensional antiferromagnet NENP are fully explained by the results.

arXiv:cond-mat/9212014•Journal of Physics Condensed Matter•Mar 1, 1993•33 citations

Distribution of exchange energy in a bond-alternating S=1 quantum spin chain

A. Zheludev, Takatsugu Masuda, B. C. Sales +4 more

The quasi-one-dimensional bond-alternating $S=1$ quantum antiferromagnet [Ni${(N,N}^{\ensuremath{'}}$$\ensuremath{-}\mathrm{b}\mathrm{i}\mathrm{s}(3\mathrm{a}\mathrm{m}\mathrm{i}\mathrm{n}\mathrm{o}\mathrm{p}\mathrm{r}\mathrm{o}\mathrm{p}\mathrm{y}\mathrm{l})\mathrm{p}\mathrm{r}\mathrm{o}\mathrm{p}\mathrm{a}\mathrm{n}\mathrm{e}\ensuremath{-}1,3\ensuremath{-}\mathrm{d}\mathrm{i}\mathrm{a}\mathrm{m}\mathrm{i}\mathrm{n}\mathrm{e}(\ensuremath{\mu}\ensuremath{-}{\mathrm{NO}}_{2})]{\mathrm{ClO}}_{4}$ (NTENP) is studied by single-crystal inelastic neutron scattering. Parameters of the measured dispersion relation for magnetic excitations are compared to existing numerical results and used to determine the magnitude of bond-strength alternation. The measured neutron-scattering intensities are also analyzed, using the first-moment sum rules for the magnetic dynamic structure factor, to directly determine the modulation of ground-state exchange energies. These independently determined modulation parameters characterize the level of spin dimerization in NTENP. First-principles density-matrix renormalization-group calculations are used to study the relation between these two quantities.

arXiv:cond-mat/0310741•Physical Review B•Apr 16, 2004•21 citations

Dynamic structure factor [S(Q,ω)] of theS=1 quasi-one-dimensional Heisenberg antiferromagnet: Neutron-scattering study on AgVP2 S6

H. Mutka, C. Payen, P. Molinié +3 more

The spin correlations of the S=1 Heisenberg antiferromagnetic chains in ${\mathrm{AgVP}}_{2}$${\mathrm{S}}_{6}$ have been studied by neutron scattering at temperatures of the order of T\ensuremath{\sim}${10}^{\mathrm{\ensuremath{-}}2}$ J/${\mathit{k}}_{\mathit{B}}$. On the polycrystalline samples, with a careful choice of experimental conditions, we have observed a Haldane gap of ${\mathit{E}}_{\mathit{g}}$=26 meV at the antiferromagnetic point at q=\ensuremath{\pi}. The excitation spectra are consistent with a mode that has a spin-wave velocity C=150 meV and a correlation length \ensuremath{\xi}\ensuremath{\approxeq}5.5, close to C/${\mathit{E}}_{\mathit{g}}$. These results are in quantitative agreement with the predictions and numerical results on the Haldane state.

Physical Review Letters•Jul 22, 1991•75 citations

HEISENBERG ANTIFERROMAGNETIC CHAIN of SPIN S=1

O. Golinelli, Th. Jolicœur, R. Lacaze

The Heisenberg antiferromagnetic chain of spin 1 with the most general single ion anisotropy is numerically analyzed. Chains of length up to 22 sites are studied by a Lanczös method and up to 32 sites with a quantum Monte Carlo. Gaps, magnetic excitations, dynamical properties and magnetic field behaviour are obtained. The recent neutron scattering experiments on the quasi one-dimensional antiferromagnet NENP are fully explained by our results.

International Journal of Modern Physics C•Apr 1, 1994•0 citations

Continuum in the Spin-Excitation Spectrum of a Haldane Chain Observed by Neutron Scattering in CsNiCl3

Igor A. Zaliznyak, S.-H. Lee, S. V. Petrov

The spin-excitation continuum, expected to dominate the low-energy fluctuation spectrum in the Haldane spin chain around the Brillouin zone center, $q\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0$, is directly observed by inelastic magnetic neutron scattering in the $S\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1$ quasi-1D antiferromagnet ${\mathrm{CsNiCl}}_{3}$. We find that the single mode approximation fails, and that a finite energy width appears in the dynamic correlation function $S(q,\ensuremath{\omega})$ for $q\ensuremath{\lesssim}0.5\ensuremath{\pi}$. The width increases with decreasing $q$, while $S(q,\ensuremath{\omega})$ acquires an asymmetric shape qualitatively similar to that predicted for the two-magnon continuum in the nonlinear $\ensuremath{\sigma}$-model.

arXiv:cond-mat/0010049•Physical Review Letters•Jun 15, 2001•73 citations

On the dynamic structure factor in one-dimensional Heisenberg magnets

H.-J. Mikeska, W. Pesch

The authors have evaluated an expression obtained previously for the dynamical spin correlation function of a linear Heisenberg antiferromagnet. The authors discuss the results in relation to both recent neutron scattering experiments and recent computations for finite chains with S= 1 / 2 . It is concluded that contributions to the dynamical structure factor from many accumulating low-frequency excitations provide the high-frequency strength required from sum rule arguments for small wavevectors.

Journal of Physics C Solid State Physics•Jan 14, 1979•4 citations
We have measured the dynamic spin correlation function for the quasi-one-dimensional S=1 antiferromagnet NENP by inelastic magnetic neutron scattering. Long-lived excitations (\ensuremath{\omega}\ensuremath{\tau}>10) exist for 0.3\ensuremath{\pi}\ensuremath{\le}q\ifmmode \tilde{}\else ~{}\fi{}\ensuremath{\le}\ensuremath{\pi}, and within error exhuast the total moment sum rule. The dispersion relation retains the fundamental periodicity of the spin chain, explicitly demonstrating the absence of broken translational symmetry in the ground state. The instantaneous spin correlation function follows a square-root Lorentzian for q\ifmmode \tilde{}\else ~{}\fi{}\ensuremath{\simeq}\ensuremath{\pi} but deviates substantially from this form for q\ifmmode \tilde{}\else ~{}\fi{}0.8\ensuremath{\pi}.
The authors study the dynamic spin correlation function of a spin-1 antiferromagnetic chain with easy-plane single-ion anisotropy. They use exact diagonalization by the Lanczos method for chains of length up to N=16 spins. They show that a single-mode approximation is an excellent description of the dynamical properties. A variational calculation allows them to clarify the nature of the excitations. The existence of a two-particle continuum near-zero wavevector is clearly seen, both in finite-size effects and in the dynamical structure factor. The recent neutron scattering experiments on the quasi-one-dimensional antiferromagnet NENP are fully explained by the results.
The quasi-one-dimensional bond-alternating S=1S=1S=1 quantum antiferromagnet [Ni${(N,N}^{\ensuremath{'}}$$\ensuremath{-}\mathrm{b}\mathrm{i}\mathrm{s}(3\mathrm{a}\mathrm{m}\mathrm{i}\mathrm{n}\mathrm{o}\mathrm{p}\mathrm{r}\mathrm{o}\mathrm{p}\mathrm{y}\mathrm{l})\mathrm{p}\mathrm{r}\mathrm{o}\mathrm{p}\mathrm{a}\mathrm{n}\mathrm{e}\ensuremath{-}1,3\ensuremath{-}\mathrm{d}\mathrm{i}\mathrm{a}\mathrm{m}\mathrm{i}\mathrm{n}\mathrm{e}(\ensuremath{\mu}\ensuremath{-}{\mathrm{NO}}_{2})]{\mathrm{ClO}}_{4}$ (NTENP) is studied by single-crystal inelastic neutron scattering. Parameters of the measured dispersion relation for magnetic excitations are compared to existing numerical results and used to determine the magnitude of bond-strength alternation. The measured neutron-scattering intensities are also analyzed, using the first-moment sum rules for the magnetic dynamic structure factor, to directly determine the modulation of ground-state exchange energies. These independently determined modulation parameters characterize the level of spin dimerization in NTENP. First-principles density-matrix renormalization-group calculations are used to study the relation between these two quantities.
The spin correlations of the S=1 Heisenberg antiferromagnetic chains in AgVP2{\mathrm{AgVP}}_{2}AgVP2​S6{\mathrm{S}}_{6}S6​ have been studied by neutron scattering at temperatures of the order of T\ensuremath{\sim}${10}^{\mathrm{\ensuremath{-}}2}$ J/kB{\mathit{k}}_{\mathit{B}}kB​. On the polycrystalline samples, with a careful choice of experimental conditions, we have observed a Haldane gap of Eg{\mathit{E}}_{\mathit{g}}Eg​=26 meV at the antiferromagnetic point at q=\ensuremath{\pi}. The excitation spectra are consistent with a mode that has a spin-wave velocity C=150 meV and a correlation length \ensuremath{\xi}\ensuremath{\approxeq}5.5, close to C/Eg{\mathit{E}}_{\mathit{g}}Eg​. These results are in quantitative agreement with the predictions and numerical results on the Haldane state.
The spin-excitation continuum, expected to dominate the low-energy fluctuation spectrum in the Haldane spin chain around the Brillouin zone center, q=0q\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0q=0, is directly observed by inelastic magnetic neutron scattering in the S=1S\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1S=1 quasi-1D antiferromagnet CsNiCl3{\mathrm{CsNiCl}}_{3}CsNiCl3​. We find that the single mode approximation fails, and that a finite energy width appears in the dynamic correlation function $S(q,\ensuremath{\omega})$ for $q\ensuremath{\lesssim}0.5\ensuremath{\pi}$. The width increases with decreasing qqq, while $S(q,\ensuremath{\omega})$ acquires an asymmetric shape qualitatively similar to that predicted for the two-magnon continuum in the nonlinear $\ensuremath{\sigma}$-model.
The authors have evaluated an expression obtained previously for the dynamical spin correlation function of a linear Heisenberg antiferromagnet. The authors discuss the results in relation to both recent neutron scattering experiments and recent computations for finite chains with S= 1 / 2 . It is concluded that contributions to the dynamical structure factor from many accumulating low-frequency excitations provide the high-frequency strength required from sum rule arguments for small wavevectors.