Francesco Macheda "Interactions between electrons and nuclear vibrations in crystals: learning from the comparison between ab-initio theoretical descriptions and experiments" Dip. di Fisica [CHIAMATA]
Il giorno 24 novembre ore 12.00 tramite collegamento zoom
Si terrà il seminario del DR. Francesco Macheda, vincitore procedura selettiva RTDA 145/23 FIS03 02B2
Interactions between electrons and nuclear vibrations in crystals: learning from the comparison between ab-initio theoretical descriptions and experiments.
The interactions between the electronic and vibrational degrees of freedom of a crystal (phonons) are at the basis of a vast ensemble of physical phenomena that emerge for matter in the solid state. Exemplarily, the electron-phonon coupling is beyond the ubiquitous display of resistance to electric current flow in materials, as well as its complete absence in the superconducting state. In this talk, I will focus on the ab-initio theoretical predictions of electronic transport coefficients, Raman scattering, and electronic energy loss spectroscopy (EELS). All of these phenomena are inherently related to the response of a crystal to external perturbing probes and can be described by appropriate response coefficients in the linear response theory framework. I will discuss the most recent advances in the comprehension of such phenomena in terms of the coupling between electrons and phonons and, finally, how the successes and failures of the ab-initio methodology in comparing with experimental data let us take a deeper look into the physics of crystalline matter.