In many-body perturbation theory, collective excitations play a predominant role in understanding structural, electronic, and vibrational properties of matter. For instance, phonons, collective modes of ions, are instrumental for electrical resistivity, band gap renormalizations, thermal conductivity, structural phase transitions, charge density waves, and superconductivity. Plasmons, collective electronic excitations, are crucial in comprehending optical properties, but can also compete and interact with phonons and, therefore, influence ordered phases.  In this talk I will present an overview of my work addressing these collective excitations in real materials, from the density-functional-theory point of view. A particular emphasis will be on the dynamical (nonadiabatic) effects of phonons and electron-phonon coupling, role of dynamical screening, plasmon-phonon coupling, dissipative effects, and ultrafast non-equilibrium dynamics. These dynamical aspects are investigated in a number of bulk and quasi-two-dimensional materials relevant in condensed matter physics and material science, such as graphene, transition metal dichalcogenides, magnesium diboride, and metal surfaces. In order to underline the developed methodologies and the outcome of my theoretical studies, I will single out the results of three projects, namely, transient vibrational relaxation of ordered molecules on metal surfaces, nonadiabatic renormalization of electron-phonon coupling in conventional superconductors, and ultrafast dynamics of Dirac plasmon in graphene. Finally, the presentation will also contain my future scientific and funding plans.

Poveznica putem koje se može pratiti predavanje:

https://us06web.zoom.us/j/89982844098?pwd=RHlkSHY1djlieThuSTVUajdZNTEzZz09

Meeting ID: 899 8284 4098

Passcode: 730111