Speaker
Description
Coherent phonons offer a powerful means to manipulate structural and electronic properties of materials on ultrafast timescales, enabling control of light-induced phase transitions and non-equilibrium dynamical phenomena.
We develop an $\textit{ab initio}$ framework to describe the excitation of coherent phonons in semimetals by combining electron-phonon coupling calculations and the time-dependent Boltzmann equation [1]. Our approach enables us to accurately model light-induced structural changes and transient band-structure renormalization following photo-excitation [2]. To illustrate its predictive capability, we investigate the fingerprints of coherent phonons in antimony (Sb) and tungsten ditelluride (WTe$\mathrm{_2}$) through a combination of tr-ARPES measurements and simulations. The robust agreement between the photoemission experiments and theory validates our methodology and highlights new opportunities to control structural and electronic degrees of freedom in semimetals via coherent phonon excitation.
[1] F. Caruso and D. Novko. Adv. Phys. X 7, 2095925 (2022)
[2] C. Emeis, et al. arXiv:2407.17118 (2024)