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arXiv · 2411.07092

Improved entanglement entropy estimates from filtered bitstring probabilities

Avi Kaufman·James Corona·Zane Ozzello·Blake Senseman·Muhammad Asaduzzaman·Yannick Meurice
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Abstract

Using the bitstring probabilities of ground states of bipartitioned ladders of Rydberg atoms, we calculate the mutual information, which is a lower bound on the corresponding bipartite von Neumann quantum entanglement entropy $S^{vN}_A$. We show that in many cases these lower bounds can be improved by removing the bitstrings with a probability lower than some value $p_{min}$ and renormalizing the remaining probabilities (filtering). We propose a heuristic based on the change of the conditional entropy under filtering that very effectively improves the estimate of $S^{vN}_A$. We consider various sizes, lattice spacings and bipartitions. Our numerical investigation suggest that the filtered mutual information obtained with samples having just a few thousand bitstrings can provide reasonably close estimates of $S^{vN}_A$. We briefly discuss practical implementations with QuEra's Aquila device.

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Avi Kaufman, James Corona, Zane Ozzello, Blake Senseman, Muhammad Asaduzzaman, Yannick Meurice. 2024-11-11. Improved entanglement entropy estimates from filtered bitstring probabilities. https://arxiv.org/abs/2411.07092

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