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arXiv · 2411.08736

Topological Phase Transitions in a Constrained Two-Qubit Quantum Control Landscape

Nicolò Beato·Pranay Patil·Marin Bukov
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Abstract

In optimal quantum control, control landscape phase transitions (CLPTs) indicate sharp changes occurring in the set of optimal protocols, as a physical model parameter is varied. Here, we demonstrate the existence of a new class of CLPTs, associated with changes in the topological properties of the optimal level set in a two-qubit state-preparation problem. In particular, the distance distribution of control protocols sampled through stochastic homotopic dynamics reveals discontinuous changes in the number of connected components in the optimal level set, as a function of the protocol duration. We demonstrate how topological CLPTs can be detected in modern-day experiments.

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Nicolò Beato, Pranay Patil, Marin Bukov. 2024-11-13. Topological Phase Transitions in a Constrained Two-Qubit Quantum Control Landscape. https://doi.org/10.1103/dqvj-p6fq

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