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arXiv · 1710.07696

Quantum dynamics from a numerical linked cluster expansion

Ian G. White·Bhuvanesh Sundar·Kaden R. A. Hazzard
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Abstract

We demonstrate that a numerical linked cluster expansion method is a powerful tool to calculate quantum dynamics. We calculate the dynamics of the magnetization and spin correlations in the two-dimensional transverse field Ising and XXZ models evolved from a product state. Such dynamics are directly probed in ongoing experiments in ultracold atoms, molecules, and ions. We show that a numerical linked cluster expansion gives dramatically more accurate results at short-to-moderate times than exact diagonalization, and simultaneously requires fewer computational resources. More specifically, the cluster expansion frequently produces more accurate results than an exact diagonalization calculation that would require $10^{5}$--$10^{10}$ more computational operations and memory.

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Ian G. White, Bhuvanesh Sundar, Kaden R. A. Hazzard. 2017-10-20. Quantum dynamics from a numerical linked cluster expansion. https://arxiv.org/abs/1710.07696

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