Ultrafast lattice-bonding dynamics of tellurium

Summary form only given. In this paper we present a study of the ultrafast bonding dynamics of tellurium in the presence of a symmetry-preserving coherent phonon. The coherent phonon modulates the band structure at THz frequencies. We measure the dielectric function, because it is closely related to the band structure, over a broad frequency range following excitation by an 800-nm, 50-fs pump pulse. We observe ultrafast changes in the bonding-antibonding split that are on the order of the band gap, offering the possibility of a band-crossing transition driven at THz frequencies.