Speaker
Description
We consider the square lattice S=½ quantum compass model (QCM) parameterized by
Jx, Jz, under an in-plane field. At the special field value,
(hx,hz)=2S(Jx,Jz), we show that the QCM Hamiltonian may be written in a
form such that two simple product states can be identified as exact
ground-states, below a gap. Exact excited states can also be found. The exact
product states are characterized by a staggered vector chirality, attaining a
non-zero value in the surrounding phase. The resulting gapped phase occupies
most of the in-plane field phase diagram but is clearly distinct from the
high field polarized phase. Using iDMRG and iPEPS techniques in combination
with exact diagonalizations and analytical arguments, we determine the
complete in-plane field phase diagram [1]. Our findings are important for
understanding the field dependent phase diagram of materials with
predominantly directionally-dependent Ising interactions, and duality
relations connects the QCM model to the Xu-Moore model and the toric code.
| Keyword-1 | Frustrated Magnetism |
|---|---|
| Keyword-2 | Kitaev Interactions |
| Keyword-3 | Quantum Compass |
