Accueil > Français > Événements > Séminaires > Théorie de la Matière Condensée sur le Plateau

Electronic properties and electronic dynamics in topological semimetals

Alberto Crepaldi


Since the discovery of topological insulators, the field of topological materials has attracted increasing attention in the condensed matter community [1]. On the one hand, the high mobility and the spin polarization of the states at the Fermi level make those compounds promising for applications. On the other hand, the low-energy electronic properties of those materials realize exotic quasiparticles, which were only postulated in high-energy physics (Dirac and Weyl Fermions) [2, 3]. Angle-resolved photoelectron spectroscopy (ARPES) has proven to be a powerful tool to directly resolve the signature of these different topological phases. In this talk I will provide a summary of my research activity of the last years. I will introduce the concept of topological semimetals, focusing on the protection and stability of the 3D Dirac semimetal phase [4-6]. By exploiting the capability of time-resolved ARPES to study the band structure upon excitation of electrons in the unoccupied conduction band, I will show you that the electron dynamics is sensitive to the formation of Weyl points [7], and that the material band dispersion can be modified by varying the electronic screening [8].

[1] M. Z. Hasan and C. L. Kane, Rev. Mod. Phys. 82, 3045 (2010)
[2] N. P. Armitage et al., Rev. of Mod. Phys. 90, 015001 (2018)
[3] B. Bradlyn et al., Science 353, 6299 (2016)
[4] G. Manzoni et al., PRL 117, 237601 (2016)
[5] S. Roth et al., PRB 97, 165439 (2018)
[6] A. Crepaldi et al., Phys. Rev. B 95, 041408(R) (2017)
[7] A. Crepaldi et al., Phys. Rev. B 96, 241408(R) (2017)
[8] G. Gatti et al., in preparation.

Agenda

Ajouter un événement iCal