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:2101.11464 · Communications in Mathematical Physics

Dimerization in Quantum Spin Chains with O(n) Symmetry

Jakob E. Björnberg, Peter Mühlbacher, Bruno Nachtergaele, Daniel Ueltschi

Published Jul 14, 2021• 3 citations
arXivHTMLPDF

Abstract

Abstract We consider quantum spins with $$S\ge 1$$ S ≥ 1 , and two-body interactions with $$O(2S+1)$$ O ( 2 S + 1 ) symmetry. We discuss the ground state phase diagram of the one-dimensional system. We give a rigorous proof of dimerization for an open region of the phase diagram, for S sufficiently large. We also prove the existence of a gap for excitations.

DOI
10.1007/s00220-021-04148-1

Related papers

Dimerization in $O(n)$-invariant quantum spin chains

Jakob E. Björnberg, Kieran Ryan

We establish dimerization in $O(n)$-invariant quantum spin chains with large enough $n$, in a much larger region of the phase diagram than previous results. This entails identifying two distinct infinite volume ground states which are gapped, are translations by one unit of each other, and which both have exponentially decaying correlations. We show these states are the limits of finite-volume, finite temperature states as the graph tends to $\mathbb{Z}$ and temperature tends to zero in any order. Our method relies on a probabilistic representation of the quantum system in terms of random loops, and an adaptation of a method developed for loop $O(n)$ models on the hexagonal lattice by Duminil-Copin, Peled, Samotij and Spinka.

arXiv:2506.06103•Jun 6, 2025•0 citations

Dimerizations in spin- S antiferromagnetic chains with three-spin interaction

Zheng-Yuan Wang, Shunsuke C. Furuya, Masaaki Nakamura +1 more

We discuss spin-$S$ antiferromagnetic Heisenberg chains with three-spin interactions, next-nearest-neighbor interactions, and bond alternation. First, we prove rigorously that there exist parameter regions of the exact dimerized ground state in this system. This is a generalization of the Majumdar-Ghosh model to arbitrary $S$. Next, we discuss the ground-state phase diagram of the models by introducing several effective field theories and the universality classes of the transitions are described by the level-$2S$ $\mathrm{SU}(2)$ Wess-Zumino-Witten model and the Gaussian model. Finally, we determine the phase diagrams of $S=1$ and $S=3/2$ systems by using exact diagonalization and level spectroscopy.

arXiv:1311.0626•Physical Review B•Dec 23, 2013•24 citations

Long-Ranged Interacting Quantum Spin Chain with Exact Dimer State

Hiroki Nakano, Minoru Takahashi

One-dimensional S =1/2 and S =1 spin systems with interactions between not only nearest-neighbor pairs of spins but also longer-range pairs are studied. We find the necessary and sufficient conditions between the coupling constants of the interactions under which the dimer state is an eigenstate of the system. We present a sufficient condition of the dimer ground state for extracted Hamiltonians. Properties of the ground state outside the dimer phase are also discussed by means of an analytical way and numerical diagonalizations.

Journal of the Physical Society of Japan•Jan 15, 1997•8 citations

Rigorous results on a first-order phase transition in antiferromagnetic spin-1/2 coupled chains

Yang Xian

Some rigorous results are presented for a first-order quantum phase transition between the dimerized state and Haldane-type state (i.e., a state similar to the ground state of the one-dimensional spin-1 Heisenberg chain) in the spin-1/2 coupled chains with nearest-neighbor and next-nearest-neighbor Heisenberg interactions. Also presented is a class of exact excited states in both phases. A partial phase diagram of the general spin-1/2 coupled chains is discussed.

arXiv:cond-mat/9501006•Physical review. B, Condensed matter•Nov 1, 1995•77 citations

Ground-State Phase Diagram of Frustrated Anisotropic Quantum Spin Chains

Takashi Hikihara, Makoto Kaburagi, Hikaru Kawamura

Recent studies on the frustrated quantum spin chains with easy-plane anisotropy are reviewed. We are particularly interested in novel “chiral ” phases characterized by the spontaneous breaking of the parity symmetry. The ground-state phase diagrams of the chains are discussed. The low-energy properties of one-dimensional quantum spin systems with frustrating interactions have been studied extensively for many years. This is mainly because they exhibit a variety of ground-state phases accompanied with various types of spontaneous symmetry breaking, e.g., the dimer phase with the translational symmetry

•Jan 1, 2002•3 citations

Dimerization and Néel Order in Different Quantum Spin Chains Through a Shared Loop Representation

Michael Aizenman, Hugo Duminil-Copin, Simone Warzel

Abstract The ground-states of the spin-Santiferromagnetic chain $$H_{{\text {AF}}}$$ HAF with a projection-based interaction and the spin-1/2 XXZ-chain $$ H_{{\text {XXZ}}}$$ HXXZ at anisotropy parameter $$\Delta =\cosh (\lambda ) $$ Δ=cosh(λ) share a common loop representation in terms of a two-dimensional functional integral which is similar to the classical planarQ-state Potts model at $$ \sqrt{Q}= 2S+1 =2\cosh (\lambda )$$ Q=2S+1=2cosh(λ) . The multifaceted relation is used here to directly relate the distinct forms of translation symmetry breaking which are manifested in the ground-states of these two models: dimerization for $$H_{{\text {AF}}}$$ HAF at all $$S> 1/2$$ S>1/2 , and Néel order for $$ H_{{\text {XXZ}}} $$ HXXZ at $$\lambda >0$$ λ>0 . The results presented include: (i) a translation to the above quantum spin systems of the results which were recently proven by Duminil–Copin–Li–Manolescu for a broad class of two-dimensional random-cluster models, and (ii) a short proof of the symmetry breaking in a manner similar to the recent structural proof by Ray–Spinka of the discontinuity of the phase transition for $$Q>4$$ Q>4 . Altogether, the quantum manifestation of the change between $$Q=4$$ Q=4 and $$Q>4$$ Q>4 is a transition from a gapless ground-state to a pair of gapped and extensively distinct ground-states.

arXiv:2002.02543•Annales Henri Poincaré•Jun 16, 2020•10 citations
Abstract We consider quantum spins with S≥1S\ge 1S≥1 S ≥ 1 , and two-body interactions with O(2S+1)O(2S+1)O(2S+1) O ( 2 S + 1 ) symmetry. We discuss the ground state phase diagram of the one-dimensional system. We give a rigorous proof of dimerization for an open region of the phase diagram, for S sufficiently large. We also prove the existence of a gap for excitations.
Dimerization in O(n)O(n)O(n)-invariant quantum spin chains
We establish dimerization in O(n)O(n)O(n)-invariant quantum spin chains with large enough nnn, in a much larger region of the phase diagram than previous results. This entails identifying two distinct infinite volume ground states which are gapped, are translations by one unit of each other, and which both have exponentially decaying correlations. We show these states are the limits of finite-volume, finite temperature states as the graph tends to Z\mathbb{Z}Z and temperature tends to zero in any order. Our method relies on a probabilistic representation of the quantum system in terms of random loops, and an adaptation of a method developed for loop O(n)O(n)O(n) models on the hexagonal lattice by Duminil-Copin, Peled, Samotij and Spinka.
We discuss spin-SSS antiferromagnetic Heisenberg chains with three-spin interactions, next-nearest-neighbor interactions, and bond alternation. First, we prove rigorously that there exist parameter regions of the exact dimerized ground state in this system. This is a generalization of the Majumdar-Ghosh model to arbitrary SSS. Next, we discuss the ground-state phase diagram of the models by introducing several effective field theories and the universality classes of the transitions are described by the level-2S2S2S SU(2)\mathrm{SU}(2)SU(2) Wess-Zumino-Witten model and the Gaussian model. Finally, we determine the phase diagrams of S=1S=1S=1 and S=3/2S=3/2S=3/2 systems by using exact diagonalization and level spectroscopy.
One-dimensional S =1/2 and S =1 spin systems with interactions between not only nearest-neighbor pairs of spins but also longer-range pairs are studied. We find the necessary and sufficient conditions between the coupling constants of the interactions under which the dimer state is an eigenstate of the system. We present a sufficient condition of the dimer ground state for extracted Hamiltonians. Properties of the ground state outside the dimer phase are also discussed by means of an analytical way and numerical diagonalizations.
Recent studies on the frustrated quantum spin chains with easy-plane anisotropy are reviewed. We are particularly interested in novel “chiral ” phases characterized by the spontaneous breaking of the parity symmetry. The ground-state phase diagrams of the chains are discussed. The low-energy properties of one-dimensional quantum spin systems with frustrating interactions have been studied extensively for many years. This is mainly because they exhibit a variety of ground-state phases accompanied with various types of spontaneous symmetry breaking, e.g., the dimer phase with the translational symmetry
Abstract The ground-states of the spin-Santiferromagnetic chain HAFH_{{\text {AF}}}HAF​ HAF with a projection-based interaction and the spin-1/2 XXZ-chain HXXZ H_{{\text {XXZ}}}HXXZ​ HXXZ at anisotropy parameter Δ=cosh⁡(λ)\Delta =\cosh (\lambda ) Δ=cosh(λ) Δ=cosh(λ) share a common loop representation in terms of a two-dimensional functional integral which is similar to the classical planarQ-state Potts model at Q=2S+1=2cosh⁡(λ) \sqrt{Q}= 2S+1 =2\cosh (\lambda )Q​=2S+1=2cosh(λ) Q=2S+1=2cosh(λ) . The multifaceted relation is used here to directly relate the distinct forms of translation symmetry breaking which are manifested in the ground-states of these two models: dimerization for HAFH_{{\text {AF}}}HAF​ HAF at all S>1/2S> 1/2S>1/2 S>1/2 , and Néel order for HXXZ H_{{\text {XXZ}}} HXXZ​ HXXZ at λ>0\lambda >0λ>0 λ>0 . The results presented include: (i) a translation to the above quantum spin systems of the results which were recently proven by Duminil–Copin–Li–Manolescu for a broad class of two-dimensional random-cluster models, and (ii) a short proof of the symmetry breaking in a manner similar to the recent structural proof by Ray–Spinka of the discontinuity of the phase transition for Q>4Q>4Q>4 Q>4 . Altogether, the quantum manifestation of the change between Q=4Q=4Q=4 Q=4 and Q>4Q>4Q>4 Q>4 is a transition from a gapless ground-state to a pair of gapped and extensively distinct ground-states.