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arXiv · 2203.12540

String order melting of spin-1 particle chains in superconducting transmons using optimal control

Paul Kairys·Travis S. Humble
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Abstract

Utilizing optimal control to simulate a model Hamiltonian is an emerging strategy that leverages the intrinsic physics of a device with digital quantum simulation methods. Here we evaluate optimal control for probing the non-equilibrium properties of symmetry-protected topological (SPT) states simulated with superconducting hardware. Assuming a tunable transmon architecture, we cast evolution of these SPT states as a series of one- and two-site pulse optimization problems that are solved in the presence of leakage constraints. From the generated pulses, we numerical simulate time-dependent melting of the perturbed SPT string order across a six-site model with an average state infidelity of $10^{-3}$. The feasibility of these pulses as well as their efficient application indicate that high-fidelity simulations of string-order melting are within reach of current quantum computing systems.

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Paul Kairys, Travis S. Humble. 2022-03-23. String order melting of spin-1 particle chains in superconducting transmons using optimal control. https://arxiv.org/abs/2203.12540

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