Seminarium Fizyki Ciała Stałego
sala 0.06, ul. Pasteura 5
prof. Bartłomiej Graczykowski (Faculty of Physics, Adam Mickiewicz University)
Phonons to Functionality: Mechanical, Thermal, and Light-Driven Responses of Nanomaterials
Dimensionality, interfaces, and structural disorder play a crucial rolein nanomaterials' mechanical and thermal properties. In this seminar, Iwill present our experimental studies of these effects, primarily usingBrillouin light scattering and Raman spectroscopy. I will first discuss the elastic anisotropy of van der Waals crystalsand size-dependent mechanical properties of suspended nanomembranes [1].Next, I will focus on phononic and colloidal crystals, showing howperiodicity, local resonances, and disorder affect GHz phononpropagation and acoustic band gaps [2]. I will then address thermal transport, highlighting two-laser Ramanthermometry to study thermal conductivity suppression in nanostructuredmembranes and thermal rectification in silicon-based devices [3,4].Finally, I will demonstrate how light can be converted into mechanicalmotion in polydopamine- and pDAP-based nanomembranes and microactuators[5]. These examples illustrate how nanoscale structure can be used tocontrol mechanical and thermal properties and enable newfunctionalities.


