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Fixed Point of the Finite System DMRG

H. Takasaki·T. Hikihara·T. Nishino
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Abstract

The density matrix renormalization group (DMRG) is a numerical method that optimizes a variational state expressed by a tensor product. We show that the ground state is not fully optimized as far as we use the standard finite system algorithm, that uses the block structure B**B. This is because the tensors are not improved directly. We overcome this problem by using the simpler block structure B*B for the final several sweeps in the finite iteration process. It is possible to increase the numerical precision of the finite system algorithm without increasing the computational effort.

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H. Takasaki, T. Hikihara, T. Nishino. 1998-10-20. Fixed Point of the Finite System DMRG. https://doi.org/10.1143/jpsj.68.1537

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