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arXiv · 2503.04658

Quench of the electronic order in a strongly-coupled charge-density-wave system by enhanced lattice fluctuations

Manuel Tuniz·Denny Puntel·Wibke Bronsch·Francesco Sammartino·Gian Marco Pierantozzi·Riccardo Cucini·Fulvio Parmigiani·Federico Cilento
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Abstract

Charge-density-wave (CDW) materials having a strong electron-phonon coupling provide a powerful platform for investigating the intricate interplay between lattice fluctuations and a macroscopic quantum order. Using time- and angle-resolved photoemission spectroscopy (TR-ARPES), we reveal that the CDW gap closure in VTe2 is dominated by an incoherent process evolving on a sub-picosecond timescale, challenging the conventional view that the gap dynamics is primarily governed by the excitation of the CDW amplitude modes. Our findings, supported by a three-temperature model, show that the CDW gap evolution can be described by considering the population of a subset of strongly-coupled optical phonon modes, which leads to an increase in the lattice fluctuations. This microscopic framework extends beyond VTe2, offering a universal perspective for understanding the light-induced phase transition in strongly-coupled CDW systems.

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Manuel Tuniz, Denny Puntel, Wibke Bronsch, Francesco Sammartino, Gian Marco Pierantozzi, Riccardo Cucini, Fulvio Parmigiani, Federico Cilento. 2025-03-06. Quench of the electronic order in a strongly-coupled charge-density-wave system by enhanced lattice fluctuations. https://arxiv.org/abs/2503.04658

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