Generalized nonlinear sigma model approach to alternating spin chains and ladders
| Autor: | Th. Jolicoeur, Marc Bocquet |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Physics
Strongly Correlated Electrons (cond-mat.str-el) Sigma model Density matrix renormalization group Diagonal Crossover FOS: Physical sciences Condensed Matter Physics Electronic Optical and Magnetic Materials Spin chain Condensed Matter - Strongly Correlated Electrons Nonlinear system Ferromagnetism Quantum mechanics Condensed Matter::Strongly Correlated Electrons Ground state |
| Zdroj: | Scopus-Elsevier |
| ISSN: | 1434-6028 |
| DOI: | 10.1007/s100510050105 |
| Popis: | We generalize the nonlinear sigma model treatment of quantum spin chains to cases including ferromagnetic bonds. When these bonds are strong enough, the classical ground state is no longer the standard Neel order and we present an extension of the known formalism to deal with this situation. We study the alternating ferromagnetic-antiferromagnetic spin chain introduced by Hida. The smooth crossover between decoupled dimers and the Haldane phase is semi-quantitatively reproduced. We study also a spin ladder with diagonal exchange couplings that interpolates between the gapped phase of the two-leg spin ladder and the Haldane phase. Here again we show that there is good agreement between DMRG data and our analytical results. 10 pages, 5 encapsulated figures, REVTeX 3.0 |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink