Spin-polaron excitations in a doped Shastry-Sutherland model

2006/07/28 by Samir El Shawish, S. El Shawish, J. Bonča +1 · 1 citation
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Theoretical and Computational Physics #cond-mat.str-el

paper · pdf · doi:10.1103/physrevb.74.174420

5 pages, 5 figures

arxiv created 2006/07/28 · openalex publication_date 2006/11/17 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

Using variational algorithm on an infinite Shastry-Sutherland (SS) lattice we show that the introduction of a static nonmagnetic impurity into a dimerized ground state leads to a formation of a small, localized spin polaron surrounding the impurity site. Due to a particular symmetry of the SS lattice, the polaron is extremely anisotropic with a short spatial extent. The presence of nonmagnetic impurities leads to a formation of pronounced in-gap peaks in the dynamical spin structure factor, which we attribute to the spin-doublet excitations of a single unpaired spin S=1∕2 surrounded by triplet fluctuations. Our results are relevant for the description of SrCu₂(BO₃)₂ compound when doped with nonmagnetic atoms at Cu sites.

Citations

• Possibility of superconductivity in the repulsive Hubbard model on the Shastry-Sutherland lattice
• Dispersion and Symmetry of Bound States in the Shastry-Sutherland Model
• Anisotropic Superexchange Interaction and Weak Ferromagnetism

Cited by

• Theory of the Raman spectra of the Shastry-Sutherland antiferromagnetSrCu2(BO3)2doped with nonmagnetic impurities