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\title{DMRG++ Kitaev model}
\author{G.~A.}
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\[
H=\sum_{i,j,\gamma}J^\gamma_{i,j}S_i^\gamma S_j^\gamma
\]
where $i$ and $j$ are lattice sites, and $\gamma\in\{\hat{x}, \hat{y}, \hat{z}\}$ is the direction.

For a honeycomb lattice we take $J^{\gamma}_{i,j}=J_\gamma$ if $i$ and $j$ are neighbors
on a honeycomb lattice in the $\gamma$ direction, and $J^{\gamma}_{i,j}=0$ otherwise.
The model then depends on three parameters: $J_x$, $J_y$, and $J_z$.
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