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arXiv · 2501.17915

A strong-driving toolkit for topological Floquet energy pumps with superconducting circuits

Martin Ritter·David M. Long·Qianao Yue·Maya Amouzegar·Anushya Chandran·Alicia J. Kollár
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Abstract

Topological Floquet energy pumps -- which use periodic driving to create a topologically protected quantized energy current -- have been proposed and studied theoretically, but have never been observed directly. Previous work proposed that such a pump could be realized with a strongly-driven superconducting qubit coupled to a cavity. Here, we experimentally demonstrate that the proposed hierarchy of energy scales and drive frequencies can be realized using a transmon qubit. We develop an experimental toolkit to realize the adiabatic driving field required for energy pumping using coordinated frequency modulation of the transmon and amplitude modulation of an applied resonant microwave drive. With this toolkit, we measure adiabatic evolution of the qubit under the applied field for times comparable to $T_1$, which far exceed the bare qubit dephasing time. This result paves the way for direct experimental observation of topological energy pumping.

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Martin Ritter, David M. Long, Qianao Yue, Maya Amouzegar, Anushya Chandran, Alicia J. Kollár. 2025-05-19. A strong-driving toolkit for topological Floquet energy pumps with superconducting circuits. https://doi.org/10.1103/syst-93sh

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