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arXiv · 1905.11430

Treelike interactions and fast scrambling with cold atoms

Gregory Bentsen·Tomohiro Hashizume·Anton S. Buyskikh·Emily J. Davis·Andrew J. Daley·Steven S. Gubser·Monika Schleier-Smith
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Abstract

We propose an experimentally realizable quantum spin model that exhibits fast scrambling, based on non-local interactions which couple sites whose separation is a power of 2. By controlling the relative strengths of deterministic, non-random couplings, we can continuously tune from the linear geometry of a nearest-neighbor spin chain to an ultrametric geometry in which the effective distance between spins is governed by their positions on a tree graph. The transition in geometry can be observed in quench dynamics, and is furthermore manifest in calculations of the entanglement entropy. Between the linear and treelike regimes, we find a peak in entanglement and exponentially fast spreading of quantum information across the system. Our proposed implementation, harnessing photon-mediated interactions among cold atoms in an optical cavity, offers a test case for experimentally observing the emergent geometry of a quantum many-body system.

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Gregory Bentsen, Tomohiro Hashizume, Anton S. Buyskikh, Emily J. Davis, Andrew J. Daley, Steven S. Gubser, Monika Schleier-Smith. 2019-05-27. Treelike interactions and fast scrambling with cold atoms. https://doi.org/10.1103/physrevlett.123.130601

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