Regularized scheme of time evolution tensor network algorithms

Abstract

Regularized factorization is proposed to simulate time evolution for quantum lattice systems. Transcending the Trotter decomposition, the resulting compact structure of the propagator indicates a high-order Baker-Campbell-Hausdorff series. Regularized scheme of tensor network algorithms is then developed to determine the ground state energy for spin lattice systems with Heisenberg or Kitaev-type interactions. Benchmark calculations reveal two distinct merits of the regularized algorithm: it has stable convergence, immune to the bias even in applying the simple update method to the Kitaev spin liquid; contraction of the produced tensor network can converge rapidly with much lower computing cost, relaxing the bottleneck to calculate the physical expectation value.

4 pages, 2 figures, 2 tables, plus 2 pages appendix