Related papers: Ultrafast lattice deformations studied by means of…
The ultrafast structural response of a thin iron film to sub-ps pulsed laser-induced heating has been investigated using time-resolved X-ray diffraction in the partial melting regime. A tetragonal distortion of the bcc-phase emerges at ~6…
The ultrafast dynamics of magnetic order in a ferromagnet are governed by the interplay between electronic, magnetic and lattice degrees of freedom. In order to obtain a microscopic understanding of ultrafast demagnetization, information on…
The ability to synthesize and control two-dimensional (2D) crystals creates numerous opportunities for studying emergent states of matter and their novel functionalities. Freestanding films provide a particularly versatile platform for…
We explore the influence of the nanoporous structure on the thermal relaxation of electrons and holes excited by ultrashort laser pulses ($\sim 7$ fs) in thin gold films. Plasmon decay into hot electron-hole pairs results in the generation…
Nonradiative processes limit optoelectronic functionality of nanocrystals and curb their device performance. Nevertheless, the dynamic structural origins of nonradiative relaxations in nanocrystals are not understood. Here, femtosecond…
In this work, we systematically investigated the ultrafast optical properties of aluminum (Al) thin films on silicon cantilevers using a microscopic femtosecond optical pump-probe technique to explore the effect of light irradiation upon…
Theory predicts that with an ultrashort and extremely bright coherent X-ray pulse, a single diffraction pattern may be recorded from a large macromolecule, a virus, or a cell before the sample explodes and turns into a plasma. Here we…
Experimental characterization and comparison of the temporal features of plasma produced by ultrafast (100 fs, 800 nm) and short-pulse (7ns, 1064 nm) laser pulses from a high purity nickel and zinc targets, expanding into a nitrogen…
Recent progress in laser wakefield acceleration has led to the emergence of a new generation of electron and X-ray sources that may have enormous benefits for ultrafast science. These novel sources promise to become indispensable tools for…
Materials modelling and processing require experiments to visualize and quantify how external excitations drive the evolution of deep subsurface structure and defects that determine properties. Today, 3D movies with ~100-nm resolution of…
Ultrafast-optical-pump -- structural-probe measurements, including ultrafast electron and x-ray scattering, provide direct experimental access to the fundamental timescales of atomic motion, and are thus foundational techniques for studying…
The interaction of ultrashort laser pulses with thin tungsten and tantalum films is investigated through the full-potential band-structure calculations. Our calculations show that at relatively low absorbed energies (the electron…
The transition between different states in manganites can be driven by various external stimuli. Controlling these transitions with light opens the possibility to investigate the microscopic path through which they evolve. We performed…
Ultrafast laser excitation of a metal causes correlated, highly nonequilibrium dynamics of electronic and ionic degrees of freedom, which are however only poorly captured by the widely-used two-temperature model. Here we develop an…
Exciting electrons in solids with intense light pulses offers the possibility of generating new states of matter through nonthermal means and controlling their macroscopic properties on femto- to picosecond timescales. One way to manipulate…
Ultrafast heat transport in nanoscale metal multilayers is of great interest in the context of optically-induced demagnetization, remagnetization and switching. We investigate the structural response and the energy flow in the ultrathin…
In past decades, ultrafast spin dynamics in magnetic systems have been associated with heat deposition from high energy laser pulses, limiting the selective access to spin order. Here we use a long wavelength terahertz pump optical probe…
Two-dimensional moir\'e materials are formed by artificially stacking atomically thin monolayers. A wealth of correlated and topological quantum phases can be engineered via precise choice of stacking geometry. These designer electronic…
Current advances in ultrafast electron microscopy make it possible to combine optical pumping of a nanostructure and electron beam probing with sub{\aa}ngstrom and femtosecond spatiotemporal resolution. We present a theory predicting that…
Extreme electron-ion non-equilibrium states, generated by ultrafast laser excitation, lead to melting processes that are fundamentally different from those under conventional thermal equilibrium and remain not fully understood. Through…