The phase transition of VO 2 from a monoclinic insulator to a rutile metal, which occurs
thermally at TC= 340 K, can also be driven by strong photoexcitation. The ultrafast dynamics …

The impulsive excitation and phase-sensitive detection of coherent phonons and phonon-
polaritons provide a detailed insight into the dynamical properties of matter. The …

We apply ultrafast spectroscopy to establish a time-domain hierarchy between structural and
electronic effects in a strongly correlated electron system. We discuss the case of the model …

We present an overview of experimental work and discuss the theory of femtosecond-pulse
generation of coherent optical phonons. Recent developments and differences between …

The electronic and structural properties of a material are strongly determined by its
symmetry. Changing the symmetry via a photoinduced phase transition offers new ways to …

Ultrafast laser spectroscopy has been used to characterize the low frequency acoustic
breathing modes of Au particles, with diameters between 8 and 120 nm. It is shown that …

We have investigated the dynamical properties of the coherent anharmonic phonons
generated in Bi under high density excitation. The time-resolved reflectivity in the intensely …

We investigate the dynamics of coherent optical phonons in tellurium after high-density
excitation with femtosecond laser pulses. The data show a continuous redshift of the phonon …

The dynamics of collective excitations of electrons, phonons, and spins are of fundamental
interest to develop a microscopic understanding of interactions among elementary …

A class of chalcogenide alloy materials that shows significant changes in optical properties
upon an amorphous-to-crystalline phase transition has lead to development of large data …