Séminaire
Vendredi 8 Novembre 2019 à 11h00.
Phonon Correlation Length in 2D-systems
Rafael Silva ALENCAR
(Université Fédéral du Piauí, Bélem, Brésil)
salle de séminaire Lippmann
Invité(e) par
Alfonso San Miguel
présentera en 1 heure :
''The knowledge of the phonon coherence length is of great importance for two-dimensional-based materials since phonons can limit the lifetime of charge carriers and heat dissipation. Here we use tip-enhanced Raman spectroscopy (TERS) to measure the spatial correlation length, Lc, in the case of monolayer and few-layer gallium sulfide (GaS). We will discuss how the differences in Lc values may be responsible of the enhancements of some phonon modes as well as the effect of the number of layers on phonon coherence. The role of surface roughness will be particularly discussed.''