Resurrecting the qdeformed Haldane–Shastry model
Seminar/Forum
We present a new and simpler expression for the Hamiltonian of the qdeformation of the HaldaneShastry spin chain, which was derived by D. Uglov over two decades ago in an apparently littleknown preprint. While resembling the pairwise longrange form of the HaldaneShastry model our formula accounts for the multispin interactions obtained by Uglov. Our expression is computationally more efficient and makes hermiticity manifest. We discuss the model's properties, including its limits and qdeformed symmetries, and review the exact spectrum found by Uglov for finite spinchain length, which parallels the isotropic case up to level splitting due to the anisotropy. We outline the proof of equality with Uglov's formulation, which also uncovers a relation with the TemperleyLieb algebra, and comment on open puzzles and directions for the future.
Presenter

Dr Jules Lamers, Chalmers University of Technology