Infinite Series of Ferrimagnetic Phases Emergent from the Gapless Spin Liquid Phase of Mixed Diamond Chains

Abstract

The ground-state phases of mixed diamond chains with ($S,{\tau }^{(1)},{\tau }^{(2)})=(1/2,1/2,1)$, where $S$ is the magnitude of vertex spins, and ${\tau }^{(1)}$ and ${\tau }^{(2)}$ are those of apical spins, are investigated. The apical spins ${\tau }^{(1)}$ and ${\tau }^{(2)}$ are connected with each other by an exchange coupling $\lambda$. Other exchange couplings are set equal to unity. This model has an infinite number of local conservation laws. For large $\lambda$, the ground state is equivalent to that of the uniform spin $1/2$ chain. Hence, the ground state is a gapless spin liquid. For $\lambda \le 0$, the ground state is a Lieb-Mattis ferrimagnetic phase with spontaneous magnetization $m_{\mathrm{sp}}=1$ per unit cell. For intermediate $\lambda$, we find a series of ferrimagnetic phases with $m_{\mathrm{sp}}=1/p$ where $p$ takes positive integer values. The phases with $p\ge 2$ are accompanied by the spontaneous breakdown of the $p$-fold translational symmetry. It is suggested that the phase with arbitrarily large $p$, namely infinitesimal spontaneous magnetization, is allowed as $\lambda$ approaches the transition point to the gapless spin liquid phase.

References in corpus (3)

• Haldane Phases and Ferrimagnetic Phases with Spontaneous Translational Symmetry Breakdown in Distorted Mixed Diamond Chains with Spins 1 and 1/2
• Ground State Phase Diagram of S=1 Diamond Chains
• Ground State Phases of Distorted $S=1$ Diamond Chains

Cited by in corpus (4)

• Frustrated magnetism of spin-1/2 Heisenberg diamond and octahedral chains as a statistical-mechanical monomer-dimer problem
• Ground-State Phase Diagram of (1/2,1/2,1) Mixed Diamond Chains
• First Order Transitions Between the Gapped Spin-Liquid and Ferrimagnetic Phases in (1/2,1/2,1) Mixed Diamond Chains with Bond Alternation
• Ground-State Phase Diagram of (1/2,1/2,1) Mixed Diamond Chains with Single-Site Anisotropy