Chiral Y junction of quantum spin chains
Abstract
We study a Y junction of spin-1/2 Heisenberg chains with an interaction that breaks both time-reversal and chain exchange symmetries, but not their product nor SU(2) symmetry. The boundary phase diagram features a stable disconnected fixed point at weak coupling and a stable three-channel Kondo fixed point at strong coupling, separated by an unstable chiral fixed point at intermediate coupling. Using non-abelian bosonization and boundary conformal field theory, together with density matrix renormalization group and quantum Monte Carlo simulations, we characterize the signatures of these low-energy fixed points. In particular, we address the boundary entropy, the spin conductance and the temperature dependence of the scalar spin chirality and the magnetic susceptibility at the boundary.
Cite
@article{arxiv.1811.06794,
title = {Chiral Y junction of quantum spin chains},
author = {F. Buccheri and R. Egger and R. G. Pereira and F. B. Ramos},
journal= {arXiv preprint arXiv:1811.06794},
year = {2019}
}
Comments
67 pages, 11 figures; v2: part of the material moved to appendix, duplicated reference removed