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arXiv · 2305.03528

Ultrafast all-optical manipulation of the charge-density-wave in VTe$_{2}$

Manuel Tuniz·Davide Soranzio·Davide Bidoggia·Denny Puntel·Wibke Bronsch·Steven L. Johnson·Maria Peressi·Fulvio Parmigiani·Federico Cilento
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Abstract

The charge-density wave (CDW) phase in the layered transition-metal dichalcogenide VTe$_{2}$ is strongly coupled to the band inversion involving vanadium and tellurium orbitals. In particular, this coupling leads to a selective disappearance of the Dirac-type states that characterize the normal phase, when the CDW phase sets in. Here, by means of broadband time-resolved optical spectroscopy (TR-OS), we investigate the ultrafast reflectivity changes caused by collective and single particle excitations in the CDW ground state of VTe$_{2}$. Remarkably, our measurements show the presence of two collective (amplitude) modes of the CDW ground state. By applying a double-pulse excitation scheme, we show the possibility to manipulate these modes, demonstrating a more efficient way to control and perturb the CDW phase in VTe$_{2}$.

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Manuel Tuniz, Davide Soranzio, Davide Bidoggia, Denny Puntel, Wibke Bronsch, Steven L. Johnson, Maria Peressi, Fulvio Parmigiani, Federico Cilento. 2023-05-05. Ultrafast all-optical manipulation of the charge-density-wave in VTe$_{2}$. https://doi.org/10.1103/physrevresearch.5.043276

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