1996/09/11 by Matthias Vojta, K. W. Becker, Klaus W. Becker · 1 citation
Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic properties of thin films #Physics of Superconductivity and Magnetism #cond-mat
paper · pdf · doi:10.1103/physrevb.54.15483
published as Phys. Rev. B 54, 15483 (1996) · REVTEX, 25 pages, 7 figures (EPS), to be published in Phys. Rev. B
arxiv created 1996/09/11 · openalex publication_date 1996/12/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
We present an approach to static and dynamical properties of holes and spins in weakly doped antiferromagnets in two dimensions. The calculations are based on a recently introduced cumulant approach to ground-state properties of correlated electronic systems. The present method allows us to evaluate hole and spin-wave dispersion relations by considering hole or spin excitations of the ground state. Usually, these dispersions are found from time-dependent correlation functions. To demonstrate the ability of the approach we first derive the dispersion relation for the lowest single hole excitation at half-filling. However, the main purpose of this paper is to focus on the mutual influence of mobile holes and spin waves in the weakly doped system. It is shown that low-energy spin excitations strongly admix to the ground state. The coupling of spin waves and holes leads to a strong suppression of the staggered magnetization which cannot be explained by a simple rigid-band picture for the hole quasiparticles. Also the experimentally observed doping dependence of the spin-wave excitation energies can be understood within our formalism.