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arXiv · 2202.04973

Floquet-Landau-Zener interferometry: Usefulness of the Floquet theory in pulse-laser-driven systems

Tatsuhiko N. Ikeda·Satoshi Tanaka·Yosuke Kayanuma
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Abstract

We develop the Landau-Zener transfer matrix theory for the instantaneous Floquet states (IFSs) for quantum systems driven by strong pulse lasers. Applying this theory to the pulse excitation probability in two-level quantum systems, we show unexpectedly good quantitative agreements for few-cycle pulses. This approach enables us to qualitatively understand the probability's peculiar behaviors as quantum path interference between IFSs. We also study the pulse-width dependence, finding that this Floquet-state interpretation remains useful for shorter pulses down to 2-cycle ones in the present model. These results imply that the Floquet theory is meaningful in experimental few-cycle lasers if applied appropriately in the sense of IFSs.

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Tatsuhiko N. Ikeda, Satoshi Tanaka, Yosuke Kayanuma. 2022-02-10. Floquet-Landau-Zener interferometry: Usefulness of the Floquet theory in pulse-laser-driven systems. https://doi.org/10.1103/physrevresearch.4.033075

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