Electron correlations in stripe phases for doped antiferromagnets

Citation
D. Gora et al., Electron correlations in stripe phases for doped antiferromagnets, PHYS REV B, 60(10), 1999, pp. 7429-7439
Citations number
41
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B-CONDENSED MATTER
ISSN journal
01631829 → ACNP
Volume
60
Issue
10
Year of publication
1999
Pages
7429 - 7439
Database
ISI
SICI code
0163-1829(19990901)60:10<7429:ECISPF>2.0.ZU;2-E
Abstract
We present the charge and magnetization density distribution in various str ipe phases obtained for two-dimensional models of correlated electrons solv ed within the Hartree-Fock approximation and a variational local ansatz. Ap art from the Hubbard model with local Coulomb interaction U, we investigate its two extensions by adding either static Peierls electron-lattice coupli ng, or the correlated hopping term in the so-called Hirsch model. It has be en found that the stripe ordering is robust and occurs in underdoped (delta = 1/8) and overdoped( delta = 1/4) systems. At intermediate values of U in underdoped systems (delta = 1/8) local correlations stabilize the vertical (01) antiferromagnetic domains, separated by nonmagnetic domain walls fill ed by one doped hole per two wall atoms. A stripe phase with the same size of magnetic domains and an increased filling of one hole per one wall atom is stable for overdoped (delta = 1/4) systems. At larger values of U, both structures are replaced by more extended magnetic domain walls oriented alo ng the (11) direction. These findings agree qualitatively with the experime ntal results. [S0163-1829(99)13733-0].