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arXiv · 1902.05664

Entanglement entropy and computational complexity of the Anderson impurity model out of equilibrium II: driven dynamics

Zhuoran He·Andrew J. Millis
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Abstract

We study the growth of entanglement entropy and bond dimension with time in density matrix renormalization group simulations of the periodically driven single-impurity Anderson model. The growth of entanglement entropy is found to be related to the ordering of the bath orbitals in the matrix product states of the bath and to the relation of the driving period $T$ to the convergence radius of the Floquet-Magnus expansion. Reordering the bath orbitals in the matrix product state by their Floquet quasi-energy is found to reduce the exponential growth rate of the computation time at intermediate driving periods, suggesting new ways to optimize matrix product state calculations of driven systems.

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Zhuoran He, Andrew J. Millis. 2019-02-15. Entanglement entropy and computational complexity of the Anderson impurity model out of equilibrium II: driven dynamics. https://doi.org/10.1103/physrevb.99.205138

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