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arXiv · 2505.07612

Time evolution of the quantum Ising model in two dimensions using Tree Tensor Networks

Wladislaw Krinitsin·Niklas Tausendpfund·Markus Heyl·Matteo Rizzi·Markus Schmitt
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Abstract

The numerical simulation of two-dimensional quantum many-body systems away from equilibrium constitutes a major challenge for all known computational methods. We investigate the utility of Tree Tensor Network (TTN) states to solve the dynamics of the quantum Ising model in two dimensions. Within the perturbative regime of small transverse fields, TTNs faithfully reproduce analytically known, but non-trivial and physically interesting results, for lattices up to $16 \times 16$ sites. Limitations of the method related to the rapid growth of entanglement entropy are explored within more general, paradigmatic quench settings. We provide and discuss comprehensive benchmarks regarding the benefit of \emph{GPU} acceleration and the impact of using local operator sums on the performance.

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Wladislaw Krinitsin, Niklas Tausendpfund, Markus Heyl, Matteo Rizzi, Markus Schmitt. 2025-05-12. Time evolution of the quantum Ising model in two dimensions using Tree Tensor Networks. https://arxiv.org/abs/2505.07612

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