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arXiv · 2407.11110

Subdiffusive transport in the Fredkin dynamical universality class

Catherine McCarthy·Hansveer Singh·Sarang Gopalakrishnan·Romain Vasseur
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Abstract

We identify a pseudolocal conserved charge in the Fredkin and Motzkin quantum spin chains and explore its consequences for the hydrodynamics of systems with Fredkin- or Motzkin-type kinetic constraints. We use this quantity to formulate an exact upper bound ${\cal O}(L^{-5/2})$ on the gap of the Fredkin and Motzkin spin chains. Our results establish that transport in kinetically constrained dynamical systems with Fredkin or Motzkin constraints is subdiffusive, with dynamical exponent $z \geq 5/2$.

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Catherine McCarthy, Hansveer Singh, Sarang Gopalakrishnan, Romain Vasseur. 2024-07-15. Subdiffusive transport in the Fredkin dynamical universality class. https://doi.org/10.1103/physrevb.111.184317

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