Hidden string order in a hole-superconductor with extended correlated hopping
Abstract
Ultracold fermions in a one-dimensional, spin-dependent, optical lattice are described by a non-standard Hubbard model with next-nearest-neighbour correlated hopping. Periodic driving of the lattice allows wide tuning of the system parameters. We solve this model exactly for a special value of the correlated hopping. The solution reveals the general properties of this system for arbitrary filling: exact and asymmetric spin-charge separation, a gapless spectrum of lowest energy excitations, a spin-gap, which may be interpreted in terms of collective hole pairing and a non-vanishing den Nijs-Rommelse type string correlator. Numerical studies away from the integrable point show the persistence of both long range string order and spin-gap.
Keywords
Cite
@article{arxiv.1508.00404,
title = {Hidden string order in a hole-superconductor with extended correlated hopping},
author = {Ravindra W. Chhajlany and Przemysław R. Grzybowski and Julia Stasińska and Maciej Lewenstein and Omjyoti Dutta},
journal= {arXiv preprint arXiv:1508.00404},
year = {2016}
}
Comments
5+2 pages