Spin-orbital gap of multiorbital antiferromagnet
Abstract
In order to discuss the spin-gap formation in a multiorbital system, we analyze an e_g-orbital Hubbard model on a geometrically frustrated zigzag chain by using a density-matrix renormalization group method. Due to the appearance of a ferro-orbital arrangement, the system is regarded as a one-orbital system, while the degree of spin frustration is controlled by the spatial anisotropy of the orbital. In the region of strong spin frustration, we observe a finite energy gap between ground and first-excited states, which should be called a spin-orbital gap. The physical meaning is clarified by an effective Heisenberg spin model including correctly the effect of the orbital arrangement influenced by the spin excitation.
Keywords
Cite
@article{arxiv.cond-mat/0604076,
title = {Spin-orbital gap of multiorbital antiferromagnet},
author = {Hiroaki Onishi and Takashi Hotta},
journal= {arXiv preprint arXiv:cond-mat/0604076},
year = {2015}
}
Comments
8 pages, 6 figures, extended version