Renormalized Classical Theory of Quantum Magnets

2023/04/08 by David Dahlbom, Hao Zhang, Dahlbom, David +9 · 5 citations
Physics and Astronomy · #Advanced Condensed Matter Physics #FOS: Physical sciences #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Strongly Correlated Electrons (cond-mat.str-el)

paper · pdf · doi:10.48550/arxiv.2304.03874

openalex publication_date 2023/04/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/03

Abstract

We derive a renormalized classical spin (RCS) theory for S > 1/2 quantum magnets by constraining a generalized classical theory that includes all multipolar fluctuations to a reduced CP¹ phase space of dipolar SU(2) coherent states. When the spin Hamiltonian \calH^S is linear in the spin operators \boldsymbolS_j for each lattice site j, the RCS Hamiltonian \calH_{\rm cl} coincides with the usual classical model \calH_{\rm cl} = lim_S→∞ \calH^S. In the presence of non-linear terms, however, the RCS theory is more accurate than \calH_{\rm cl}. For the many materials modeled by spin Hamiltonians with (non-linear) single-ion anisotropy terms, the use of the RCS theory is essential to accurately model phase diagrams and to extract the correct Hamiltonian parameters from neutron scattering data

Cited by

• Kitaev interactions of the spin-orbit coupled magnet UO2
• Single-ion anisotropy driven chiral magnetic order in a spin-1 antiferromagnetic chain
• Nonperturbative Semiclassical Spin Dynamics for Ordered Quantum Magnets
• Electron-phonon coupled Langevin dynamics for Mott insulators
• Skyrmions of Frustrated Quantum Dimer Systems

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