Detecting a Z2 topologically ordered phase from unbiased infinite projected entangled-pair state simulations

  title={Detecting a 
 topologically ordered phase from unbiased infinite projected entangled-pair state simulations},
  author={Sven Crone and Philippe Corboz},
  journal={Physical Review B},
We present an approach to identify topological order based on unbiased infinite projected entangled-pair states (iPEPS) simulations, i.e. where we do not impose a virtual symmetry on the tensors during the optimization of the tensor network ansatz. As an example we consider the ground state of the toric code model in a magnetic field exhibiting $Z_2$ topological order. The optimization is done by an efficient energy minimization approach based on a summation of tensor environments to compute… 

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