Manipulation of the charge-density-wave in VTe2 ‌by femtosecond light pulses

M. Tuniz,1 W. Bronsch,2 D. Puntel,1 D. Soranzio,3 D. Bidoggia,1
M. Peressi,1 F. Parmigiani,1,2 F. Cilento2

1Dipartimento di Fisica, Università degli Studi di Trieste, Italy

2Elettra – Sincrotrone Trieste S.C.p.A., Italy

3Institute for Quantum Electronics, ETH Zürich, 8093 Zurich, Switzerland.

By combining time and angle-resolved photoemission spectroscopy (tr-ARPES) and broadband time-resolved optical spectroscopy (TR-OS) we investigate the effect of an optical excitation on the electronic and structural properties of the charge-density wave (CDW) system VTe2. Recently, the modification of the material’s electronic structure induced by CDW formation has been discussed because the strongly orbital-dependent changes may give rise to a topological change in specific bands [1].

In our contribution, we show by means of TR-OS measurements the possibility to optically excite the amplitude mode (AM) of the CDW phase and therefore couple to the CDW condensate [2]. Moreover, by studying the partial closing of the CDW gap our tr-ARPES experiments unveil a major role played by the lattice degrees of freedom in the stabilization of the CDW phase in VTe2.

1. Mitsuishi, N. et al. Nat Commun. 11, 2466 (2020)
2. Tuniz, M. et al. arXiv:2305.03528 (2023)