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arXiv · 2306.02571

Probing entanglement across the energy spectrum of a hard-core Bose-Hubbard lattice

Amir H. Karamlou·Ilan T. Rosen·Sarah E. Muschinske·Cora N. Barrett·Agustin Di Paolo·Leon Ding·Patrick M. Harrington·Max Hays·Rabindra Das·David K. Kim·Bethany M. Niedzielski·Meghan Schuldt·Kyle Serniak·Mollie E. Schwartz·Jonilyn L. Yoder·Simon Gustavsson·Yariv Yanay·Jeffrey A. Grover·William D. Oliver
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Abstract

Entanglement and its propagation are central to understanding a multitude of physical properties of quantum systems. Notably, within closed quantum many-body systems, entanglement is believed to yield emergent thermodynamic behavior. However, a universal understanding remains challenging due to the non-integrability and computational intractability of most large-scale quantum systems. Quantum hardware platforms provide a means to study the formation and scaling of entanglement in interacting many-body systems. Here, we use a controllable $4 \times 4$ array of superconducting qubits to emulate a two-dimensional hard-core Bose-Hubbard lattice. We generate superposition states by simultaneously driving all lattice sites and extract correlation lengths and entanglement entropy across its many-body energy spectrum. We observe volume-law entanglement scaling for states at the center of the spectrum and a crossover to the onset of area-law scaling near its edges.

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Amir H. Karamlou, Ilan T. Rosen, Sarah E. Muschinske, Cora N. Barrett, Agustin Di Paolo, Leon Ding, Patrick M. Harrington, Max Hays, Rabindra Das, David K. Kim, Bethany M. Niedzielski, Meghan Schuldt, Kyle Serniak, Mollie E. Schwartz, Jonilyn L. Yoder, Simon Gustavsson, Yariv Yanay, Jeffrey A. Grover, William D. Oliver. 2023-06-05. Probing entanglement across the energy spectrum of a hard-core Bose-Hubbard lattice. https://doi.org/10.1038/s41586-024-07325-z

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