Effect of the Orbital Level Difference in Doped Spin-1 Chains
Abstract
The doping of a two-orbital chain with mobile S=1/2 fermions andstrong Hund's rule couplings stabilizing the S=1 spins stronglydepends on the presence of a level difference among these orbitals. Using density matrix renormalization group(DMRG) methods, we find a finite spin gap upon doping and dominantpairing correlations without level difference, whereas the presence ofa level difference leads to dominant charge density wave (CDW)correlations with gapless spin-excitations. The string correlationfunction also shows qualitative differences between the two models.
- Publication:
-
Journal of the Physical Society of Japan
- Pub Date:
- July 2000
- DOI:
- 10.1143/JPSJ.69.1946
- arXiv:
- arXiv:cond-mat/0002193
- Bibcode:
- 2000JPSJ...69.1946A
- Keywords:
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- Condensed Matter
- E-Print:
- 4 pages, 4 figures