GROGU¶
Spin Hamiltonian¶
\[\mathcal{H}
=
\frac{1}{2}
\sum_{i\neq j}
\boldsymbol{e}_{i}
\cdot
\boldsymbol{J}_{ij}
\cdot
\boldsymbol{e}_{j}
+
\sum_{i}
\boldsymbol{e}_{i}
\cdot
\boldsymbol{K}_{i}
\cdot
\boldsymbol{e}_{i},\]
where \(\boldsymbol{e}_{i} = 1 / (\hbar S_i) \boldsymbol{S}_{i}\) is a unit vector of the angular momentum vector and \(\boldsymbol{J}_{ij}\), and \(\boldsymbol{K}_{i}\) are the exchange and on-site anisotropy tensors respectively.
Convention¶
Spin normalized |
yes |
Multiple counting |
yes |