Surface optical and bulk acoustic phonons in the topological insulator, Bi2Se2Te
Surface optical and bulk acoustic phonons in the topological insulator, Bi2Se2Te
We explore the phonon dynamics of thin films of the topological insulator material Bi2Se2Te using ultrafast pump-probe spectroscopy. The time resolved differential reflectivity of the films exhibit fast and slow oscillations. We have given a careful analysis of variation of phonon frequency as a function of film thickness attributing this …