1997/11/30 by R. Eder
Physics and Astronomy · #Condensed matter physics #Dynamics (music) #Magnetic confinement fusion research #Physics #Physics of Superconductivity and Magnetism #Quantum many-body systems #Spin (aerodynamics) #Statistical physics #Thermodynamics #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.57.12832
RevTex-file, 10 PRB pages with 7 eps files. Hardcopies of figures (or the entire manuscript) can be obtained by e-mail request to: [email protected]
arxiv created 1997/11/30 · openalex publication_date 1998/05/15 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We derive an approximate theory for Heisenberg spin ladders with two legs by mapping the spin dynamics onto the problem of hard-core ``bond bosons.'' The parameters of the bosonic Hamiltonian are obtained by matching anomalous Green's functions to Lanczos results and we find evidence for a strong renormalization due to quantum fluctuations. Various dynamical spin correlation functions are calculated and found to be in good agreement with Lanczos results. We then enlarge the effective Hamiltonian to describe the coupling of the bosonic spin fluctuations to a single hole injected into the system and treat the hole dynamics within the rainbow-diagram approximation of Schmitt-Rink et al. Theoretical predictions for the single-hole spectral function are obtained and found to be in good agreement with Lanczos results.