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arXiv · 2409.14442

Efficient computation of cumulant evolution and full counting statistics: application to infinite temperature quantum spin chains

Angelo Valli·Cătălin Paşcu Moca·Miklós Antal Werner·Márton Kormos·Žiga Krajnik·Tomaž Prosen·Gergely Zaránd
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Abstract

We propose a numerical method to efficiently compute quantum generating functions (QGF) for a wide class of observables in one-dimensional quantum systems at high temperature. We obtain high-accuracy estimates for the cumulants and reconstruct full counting statistics from the QGF. We demonstrate its potential on spin $S=1/2$ anisotropic Heisenberg chain, where we can reach time scales hitherto inaccessible to state-of-the-art classical and quantum simulations. Our results challenge the conjecture of the Kardar--Parisi--Zhang universality for isotropic integrable quantum spin chains.

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Angelo Valli, Cătălin Paşcu Moca, Miklós Antal Werner, Márton Kormos, Žiga Krajnik, Tomaž Prosen, Gergely Zaránd. 2024-09-22. Efficient computation of cumulant evolution and full counting statistics: application to infinite temperature quantum spin chains. https://doi.org/10.1103/f3c4-n21z

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