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arXiv · 1908.09531

Observing collisions beyond the secular approximation limit

J. Ma·H. Zhang·B. Lavorel·F. Billard·E. Hertz·J. Wu·C. Boulet·J. -M. Hartmann·O. Faucher
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Abstract

Energy transfer through quantum coherences plays an essential role in diverse natural phenomena and technological applications, such as human vision, light-harvesting complexes, quantum heat engines, and quantum information and computing. The understanding of the long-lived coherence involved in these phenomena requires a detailed modeling of the system-bath interactions beyond the so-called secular and/or Markovian approximations. Despite continuous theoretical progress on understanding nonsecular dynamics in the last decades, convincing experimental observations are still lacking. By using the laser-kicked molecular rotor as a model system, we here experimentally unveil the nonsecular dynamics in the rotational relaxation of molecules due to thermal collisions. Specifically, the rotational coherence in gas-phase molecules is systematically probed and characterized by the recently discovered rotational alignment echoes featuring a decoherence and dissipation process which can only be explained by the nonsecular quantum master equations for modeling molecular collisions.

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J. Ma, H. Zhang, B. Lavorel, F. Billard, E. Hertz, J. Wu, C. Boulet, J. -M. Hartmann, O. Faucher. 2019-08-26. Observing collisions beyond the secular approximation limit. https://doi.org/10.1038/s41467-019-13706-0

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