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arXiv · 2207.09296

Visualized Wave Mechanics by Coupled Macroscopic Pendula: Classical Analogue to Driven Quantum Bits

Heribert Lorenz·Sigmund Kohler·Anton Parafilo·Mikhail Kiselev·Stefan Ludwig
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Abstract

Quantum mechanics increasingly penetrates modern technologies but, due to its non-deterministic nature seemingly contradicting our classical everyday world, our comprehension often stays elusive. Arguing along the correspondence principle, classical mechanics is often seen as a theory for large systems where quantum coherence is completely averaged out. Surprisingly, it is still possible to reconstruct the coherent dynamics of a quantum bit (qubit) by using a classical model system. This classical-to-quantum analogue is based on wave mechanics, which applies to both, the classical and the quantum world. In this spirit we investigate the dynamics of macroscopic physical pendula with a modulated coupling. As a proof of principle, we demonstrate full control of our one-to-one analogue to a qubit by realizing Rabi oscillations, Landau-Zener transitions and Landau-Zener-St\"uckelberg-Majorana interferometry. Our classical qubit demonstrator can help comprehending and developing useful quantum technologies.

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Heribert Lorenz, Sigmund Kohler, Anton Parafilo, Mikhail Kiselev, Stefan Ludwig. 2022-07-19. Visualized Wave Mechanics by Coupled Macroscopic Pendula: Classical Analogue to Driven Quantum Bits. https://doi.org/10.1038/s41598-023-45118-y

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