From 3D to 1D systems: Emergent phenomena in phononics and thermal-radiative response.

Friday 03 June 2022, 14:00

Giorgia Fugallo

In many nanostructured materials, while strong covalent bonding provides the stability of the sub-nanometric elementary units, the whole assembly is held together by weak van der Waals interactions. The individual building blocks hence maintain most of their intrinsic characteristics also when arranged together to form a crystalline solid. In principle, novel material properties can be thus tailored by controlling those of the elementary units.
In this context, the interest in low-dimensional materials is self-evident. On the one hand, the physics of many-body systems, limited in 2D or 1D presents a plethora of unusual fascinating properties; on the other hand, the reduction of dimensionality allows us to perform gedanken experiments for testing/improving and better understanding physical models. In this talk I will show how to tackle different emergent phenomena in the phononics and thermal-radiative response of systems at different dimensionality [1-4].

Refs.
[1] T. Kang et al. " Ultrafast nonlinear phonon response of few-layer hexagonal boron
nitride ” PRB-L (2021).
[2] G. Fugallo et al "Infrared reflectance, transmittance, and emittance spectra of MgO
from first principles"Physical Review B 98 (18), 184307 (2018)
[3] G. Cassabois et al "Exciton and phonon radiative linewidths in monolayer boron
nitride"Physical Review X 12 (1), 011057" (2022)
[4] C. Melis et al. “Room Temperature Second Sound in Cumulene” Phys. Chem. Chem. Phys.
23, 15275-15281 (2021)

Video available here.