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arXiv · 2303.12111

Dissipative preparation and stabilization of many-body quantum states in a superconducting qutrit array

Abstract

We present and analyze a protocol for driven-dissipatively preparing and stabilizing a manifold of quantum manybody entangled states with symmetry-protected topological order. Specifically, we consider the experimental platform consisting of superconducting transmon circuits and linear microwave resonators. We perform theoretical modeling of this platform via pulse-level simulations based on physical features of real devices. In our protocol, transmon qutrits are mapped onto spin-1 systems. The qutrits' sharing of nearest-neighbor dispersive coupling to a dissipative microwave resonator enables elimination of state population in the $S^\mathrm{total}=2$ subspace for each adjacent pair, and thus, the stabilization of the manybody system into the Affleck, Kennedy, Lieb, and Tasaki (AKLT) state up to the edge mode configuration. We also analyze the performance of our protocol as the system size scales up to four qutrits, in terms of its fidelity as well as the stabilization time. Our work shows the capacity of driven-dissipative superconducting cQED systems to host robust and self-corrected quantum manybody states that are topologically non-trivial.

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Yunzhao Wang, Kyrylo Snizhko, Alessandro Romito, Yuval Gefen, Kater Murch. 2023-03-21. Dissipative preparation and stabilization of many-body quantum states in a superconducting qutrit array. https://doi.org/10.1103/physreva.108.013712

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