Nonbonding oxygen holes and spinless scenario of magnetic response in doped cuprates
A. S. Moskvin
Department of Theoretical Physics, Ural State University, 620083 Ekaterinburg, Russia
PACS: 74.72.-h
Abstract
Both theoretical considerations and experimental data point to a
more complicated nature of the valence hole states in doped cuprates than it
is predicted by Zhang-Rice model. Actually, we deal with a competition of
conventional hybrid Cu 3d-O 2p state and
purely oxygen nonbonding state with symmetry. The
latter reveals a non-quenched Ising-like orbital moment that gives rise to a
novel spinless purely oxygen scenario of the magnetic response in doped
cuprates with the oxygen localized orbital magnetic moments of the order of
tenths of Bohr magneton. We consider the mechanism of 63,65Cu-O 2p
transferred orbital hyperfine interactions due to the mixing of the oxygen O
2p orbitals with Cu 3p semicore orbitals. Quantitative estimates point to
a large magnitude of the respective contributions both to local field and
electric field gradient, and their correlated character.