Exact ground states of frustrated quantum spin systems consisting of spin-dimer units

Abstract

We study frustrated quantum spin systems consisting of dimers of spin-1/2 spins. We derive several models that have the exact ground state of the form of the direct product of dimer states. The ground states realized include the product state of dimer singlets, that of dimer triplets with zero magnetization, those of dimer-spin-nematic states, and those of a mixture of the dimer states. Pseudo spin-1/2 operators emerging in each dimer are also introduced.

9 pages, 4 figures, 1 table. v2: accepted version, Sec.IIIE and a few references added, some sentences revised, to appear in J. Phys. Soc. Jpn

References in corpus (7)

• Gapless spin-liquid ground state in the $S=1/2$ kagome antiferromagnet
• Vector chiral and multipolar orders in the spin-1/2 frustrated ferromagnetic chain in magnetic field
• Emergent multipolar spin correlations in a fluctuating spiral - The frustrated ferromagnetic S=1/2 Heisenberg chain in a magnetic field
• Octupolar order in the multiple spin exchange model on a triangular lattice
• Vector chiral order in frustrated spin chains
• On calculation of vector spin chirality for zigzag spin chains
• Exact non-magnetic ground state and residual entropy of S = 1/2 Heisenberg diamond spin lattices

Cited by in corpus (5)

• Spin nematics in frustrated spin-dimer systems with bilayer structure
• Ground-State Phase Diagram of an Anisotropic S=1/2 Ladder with Different Leg Interactions
• Covariance-based method for eigenstate factorization and generalized singlets
• Exact plaquette singlet phases in an orthogonal-plaquette model
• Tree-Graph Based Construction of Quantum Spin Models with Exact Ground State