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arXiv · 2208.10972

Time-dependent variational principle with controlled bond expansion for matrix product states

Jheng-Wei Li·Andreas Gleis·Jan von Delft
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Abstract

We present a controlled bond expansion (CBE) approach to simulate quantum dynamics based on the time-dependent variational principle (TDVP) for matrix product states. Our method alleviates the numerical difficulties of the standard, fixed-rank one-site TDVP integrator by increasing bond dimensions on the fly to reduce the projection error. This is achieved in an economical, local fashion, requiring only minor modifications of standard one-site TDVP implementations. We illustrate the performance of CBE--TDVP with several numerical examples on finite quantum lattices.

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Jheng-Wei Li, Andreas Gleis, Jan von Delft. 2022-08-23. Time-dependent variational principle with controlled bond expansion for matrix product states. https://doi.org/10.1103/physrevlett.133.026401

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