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arXiv · 2503.20356

Bipartite particle number fluctuations in dephased long-range lattice systems

Lokesh Tater·Subhajit Sarkar·Devendra Singh Bhakuni·Bijay Kumar Agarwalla
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Abstract

We investigate the dynamics of subsystem particle number fluctuations in a long-range system with power-law decaying hopping strength characterized by exponent $\mu$ and subjected to a local dephasing at every site. We introduce an efficient {\it bond length} representation for the four-point correlator, enabling the large-scale simulation of the dynamics of particle number fluctuations from translationally invariant initial states. Our results show that the particle number fluctuation dynamics exhibit one-parameter Family-Vicsek scaling, with superdiffusive scaling exponents for $\mu < 1.5$ and diffusive scaling exponents for $\mu \geq 1.5$. Finally, exploiting the bond-length representation, we provide an exact analytical expression for the particle number fluctuations and their scaling exponents in the short-range limit ($\mu \to \infty)$.

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Lokesh Tater, Subhajit Sarkar, Devendra Singh Bhakuni, Bijay Kumar Agarwalla. 2025-03-26. Bipartite particle number fluctuations in dephased long-range lattice systems. https://arxiv.org/abs/2503.20356

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