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arXiv · 2206.12803

A scalable superconducting quantum simulator with long-range connectivity based on a photonic bandgap metamaterial

Xueyue Zhang·Eunjong Kim·Daniel K. Mark·Soonwon Choi·Oskar Painter
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Abstract

Synthesis of many-body quantum systems in the laboratory can help provide further insight into the emergent behavior of quantum materials, whose properties may provide improved methods for energy conversion, signal transport, or information processing. While the majority of engineerable many-body systems, or quantum simulators, consist of particles on a lattice with local interactions, quantum systems featuring long-range interactions are particularly challenging to model and interesting to study due to the rapid spatio-temporal growth of quantum entanglement and correlations. Here, we present a scalable quantum simulator architecture based on a linear array of superconducting qubits locally connected to an extensible photonic-bandgap metamaterial. The metamaterial acts both as a quantum bus mediating qubit-qubit interactions, and as a readout channel for multiplexed qubit-state measurement. As an initial demonstration, we realize a 10-qubit simulator of the one-dimensional Bose-Hubbard model with in situ tunability of both the hopping range and the on-site interaction. We characterize the Hamiltonian of the system using a measurement-efficient protocol based on quantum many-body chaos. Further, we study the many-body quench dynamics of the system, revealing through global bit-string statistics the predicted crossover from integrability to ergodicity as the hopping range increases. The metamaterial quantum bus architecture presented here can be extended to two-dimensional lattice systems and used to generate a wide range of qubit interactions, expanding the accessible Hamiltonians for analog quantum simulation and increasing the flexibility in implementing quantum circuits for gate-based computations

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Xueyue Zhang, Eunjong Kim, Daniel K. Mark, Soonwon Choi, Oskar Painter. 2022-06-26. A scalable superconducting quantum simulator with long-range connectivity based on a photonic bandgap metamaterial. https://doi.org/10.1126/science.ade7651

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