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arXiv · 2107.05035

Quantum transport and localization in 1d and 2d tight-binding lattices

Amir H. Karamlou·Jochen Braumüller·Yariv Yanay·Agustin Di Paolo·Patrick Harrington·Bharath Kannan·David Kim·Morten Kjaergaard·Alexander Melville·Sarah Muschinske·Bethany Niedzielski·Antti Vepsäläinen·Roni Winik·Jonilyn L. Yoder·Mollie Schwartz·Charles Tahan·Terry P. Orlando·Simon Gustavsson·William D. Oliver
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Abstract

Particle transport and localization phenomena in condensed-matter systems can be modeled using a tight-binding lattice Hamiltonian. The ideal experimental emulation of such a model utilizes simultaneous, high-fidelity control and readout of each lattice site in a highly coherent quantum system. Here, we experimentally study quantum transport in one-dimensional and two-dimensional tight-binding lattices, emulated by a fully controllable $3 \times 3$ array of superconducting qubits. We probe the propagation of entanglement throughout the lattice and extract the degree of localization in the Anderson and Wannier-Stark regimes in the presence of site-tunable disorder strengths and gradients. Our results are in quantitative agreement with numerical simulations and match theoretical predictions based on the tight-binding model. The demonstrated level of experimental control and accuracy in extracting the system observables of interest will enable the exploration of larger, interacting lattices where numerical simulations become intractable.

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Amir H. Karamlou, Jochen Braumüller, Yariv Yanay, Agustin Di Paolo, Patrick Harrington, Bharath Kannan, David Kim, Morten Kjaergaard, Alexander Melville, Sarah Muschinske, Bethany Niedzielski, Antti Vepsäläinen, Roni Winik, Jonilyn L. Yoder, Mollie Schwartz, Charles Tahan, Terry P. Orlando, Simon Gustavsson, William D. Oliver. 2021-07-11. Quantum transport and localization in 1d and 2d tight-binding lattices. https://doi.org/10.1038/s41534-022-00528-0

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