Variational optimization of tensor-network states with the honeycomb-lattice corner transfer matrix

We develop a method of variational optimization of the infinite projected entangled pair states on the honeycomb lattice. The method is based on the automatic differentiation of the honeycomb-lattice cor-ner transfer matrix renormalization group. We apply the approach to the antiferromagnetic Heisenberg spin-1/2 and ferromagnetic Kitaev models on the honeycomb lattice. The developed formalism gives quan-titatively accurate results for the main physical observables and has a necessary potential for further extensions.

Automated summary

We have developed a method for variational optimization of the infinite projected entangled pair states on the honeycomb lattice, using automatic differentiation of the honeycomb-lattice corner transfer matrix renormalization group. We applied this method to the antiferromagnetic Heisenberg spin-1/2 and ferromagnetic Kitaev models on the honeycomb lattice. The developed formalism provides quantitatively accurate results for the main physical observables and has potential for further extensions.