Massive spinons in $S=1/2$ spin chains: spinon-pair operator representation

Abstract

Spinons are among the generic excitations in one-dimensional spin systems, they can be massless or massive. The quantitative description of massive spinons poses a considerable challenge in spite of various variational approaches. We show that a representation in terms of hopping and Bogoliubov spinon processes, which we call "spinon-pair" operators, and their combination is possible. We refer to such a representation as second quantized form. Neglecting terms which change the number of spinons yields the variational results. Treating the bilinear and quartic terms by continuous unitary transformations leads to considerably improved results. Thus, we provide the proof-of-principle that systems displaying massive spinons as elementary excitations can be treated in second quantization based on spinon-pair representation.

19 pages

References in corpus (10)

• Dirac Strings and Magnetic Monopoles in Spin Ice Dy2Ti2O7
• Herbertsmithite and the Search for the Quantum Spin Liquid
• Spinons and triplons in spatially anisotropic frustrated antiferromagnets
• Observation of Magnetic Monopoles in Spin Ice
• Roton minimum as fingerprint of magnon-Higgs scattering in ordered quantum antiferromagnets
• Effective models for gapped phases of strongly correlated quantum lattice models
• Quantum Monte Carlo studies of spinons in one-dimensional spin systems
• Excitation Spectrum of One-dimensional Extended Ionic Hubbard Model
• Spinon excitation spectra of the $J_1$-$J_2$ chain from analytical calculations in the dimer basis and exact diagonalization
• Incommensurability Effects in Odd Length J_1-J_2 Quantum Spin Chains: On-site magnetization and Entanglement

Cited by in corpus (3)

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