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arXiv · 2011.08200

Efficient Tensor Network ansatz for high-dimensional quantum many-body problems

Timo Felser·Simone Notarnicola·Simone Montangero
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Abstract

We introduce a novel tensor network structure augmenting the well-established Tree Tensor Network representation of a quantum many-body wave function. The new structure satisfies the area law in high dimensions remaining efficiently manipulatable and scalable. We benchmark this novel approach against paradigmatic two-dimensional spin models demonstrating unprecedented precision and system sizes. Finally, we compute the ground state phase diagram of two-dimensional lattice Rydberg atoms in optical tweezers observing non-trivial phases and quantum phase transitions, providing realistic benchmarks for current and future two-dimensional quantum simulations.

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Timo Felser, Simone Notarnicola, Simone Montangero. 2020-11-16. Efficient Tensor Network ansatz for high-dimensional quantum many-body problems. https://doi.org/10.1103/physrevlett.126.170603

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