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arXiv · 2207.05571

Light-induced hexatic state in a layered quantum material

Till Domröse·Thomas Danz·Sophie F. Schaible·Kai Rossnagel·Sergey V. Yalunin·Claus Ropers
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Abstract

The tunability of materials properties by light promises a wealth of future applications in energy conversion and information technology. Strongly correlated materials such as transition-metal dichalcogenides (TMDCs) offer optical control of electronic phases, charge ordering and interlayer correlations by photodoping. Here, we find the emergence of a transient hexatic state in a TMDC thin-film during the laser-induced transformation between two charge-density wave (CDW) phases. Introducing tilt-series ultrafast nanobeam electron diffraction, we reconstruct CDW rocking curves at high momentum resolution. An intermittent suppression of three-dimensional structural correlations promotes a loss of in-plane translational order characteristic of a hexatic intermediate. Our results demonstrate the merit of tomographic ultrafast structural probing in tracing coupled order parameters, heralding universal nanoscale access to laser-induced dimensionality control in functional heterostructures and devices.

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Till Domröse, Thomas Danz, Sophie F. Schaible, Kai Rossnagel, Sergey V. Yalunin, Claus Ropers. 2022-07-12. Light-induced hexatic state in a layered quantum material. https://doi.org/10.1038/s41563-023-01600-6

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