English

Long-range orders, spin- and orbital-freezing in the two-band Hubbard model

Strongly Correlated Electrons 2016-08-09 v1

Abstract

We solve the orbitally degenerate two-band Hubbard model within dynamical mean field theory and map out the instabilities to various symmetry-broken phases based on an analysis of the corresponding lattice susceptibilities. Phase diagrams as a function of the Hund coupling parameter J are obtained both for the model with rotationally invariant interaction and for the model with Ising-type anisotropy. For negative J, an intra-orbital spin-singlet superconducting phase appears at low temperatures, while the normal state properties are characterized by an orbital freezing phenomenon. This is the negative-J analogue of the recently discovered fluctuating-moment induced s-wave spin-triplet superconductivity in the spin-freezing regime of multi-orbital models with J>0.

Keywords

Cite

@article{arxiv.1605.06410,
  title  = {Long-range orders, spin- and orbital-freezing in the two-band Hubbard model},
  author = {Karim Steiner and Shintaro Hoshino and Yusuke Nomura and Philipp Werner},
  journal= {arXiv preprint arXiv:1605.06410},
  year   = {2016}
}