Search

Generalized measurements that do not correspond to conventional basis projections of the quantum wavefunction are a part of several important protocols in quantum information. These measurements can be certifiably performed on higher-dimensional systems using optical fibre technology.

Spectroscopic measurements confirm that when water is adsorbed on drops of an alkali alloy at low pressure a gold-coloured metallic layer forms as electrons rapidly move from the drop into the water.

The transition state, a transient species where bond transformation occurs, fundamentally controls reaction dynamics. This important species can be probed through the photodetachment of an anionic precursor, as has now been shown in the F + NH₃ reaction. A combination of theory and experiment reveals resonances that span the transition state.

The interactions of electrons and water molecules are not just of great fundamental interest but are also studied to understand the role electrons have in damaging biomolecules. Now using ultrafast photoelectron spectroscopy, key details about the energy and lifetime of the hydrated electron in bulk and at an interface have been determined.

Excited-state molecular dynamics may be too complex to be resolved by femtosecond spectroscopic studies. Here the authors resolve the competing pathways in the excited state dynamics of methyl bromide by attosecond transient absorption spectroscopy, from excitation to fragmentation.

Ultrafast dynamics following light-matter interaction are governed by nonlinear processes. Here the authors show that initial nonlinear signal time-evolution is a consequence of phase grating accumulation using transient grating measurements with attosecond and near-infrared pulses.

Understanding excited carrier dynamics in semiconductors is central to the continued development of optoelectronic devices. Using extreme ultraviolet transient absorption spectroscopy, Zürchet al. directly and simultaneously observe ultrafast electron and hole dynamics in germanium thin films.

The reaction trajectories of photoexcited molecules may involve transitions through conical intersections, which are ubiquitous in nature but challenging to characterize. Here the authors provide a complete mapping of molecular dissociation of two model alkyl halides by ultrafast XUV transient absorption.

Here the authors report a study measuring lifetimes of core-hole states of ICl molecule using attosecond transient absorption spectroscopy. They find that lifetimes depend on the alignment of the orbital relative to the molecular axis.

The F + para-H₂ → HF + H reaction is an important source of HF in interstellar clouds; however, its unusually high rate and its dynamics at low temperature are not fully understood. Now, quantum-state resolved crossed-beam scattering measurements and anion photoelectron spectroscopy have revealed that this reactivity is caused by a resonance-enhanced tunnelling effect involving a post-barrier resonance state.

The transition state governs how bonds form and cleave during a reaction — its direct characterization is a long-standing challenge. Now, the F + CH₃OH → HF + CH₃O reactive surface has been studied using photoelectron velocity-map imaging spectroscopy of cryo-cooled anions, revealing vibrational Feshbach resonances and bound states supported by the post-transition-state potential well. The experiments agree well with quantum dynamical calculations.

The evolution of X-ray transient absorption signal in studies of ultrafast molecular dynamics is controlled by the shapes of potential energy surfaces of the associated core-excited states. The authors use experiment and theory to measure the slopes of potential energy surfaces for excitations out of the C 1s and Cl 2p shells to valence antibonding orbitals in CCl₄

Ultrafast X-ray spectroscopies enable the investigation of fast chemical dynamics with time resolutions reaching the order of attoseconds. Processes such as spin crossover, structural deformations in excited states and dissociation reactions can now be studied through the use of short X-ray pulses produced by high-harmonic, free-electron-laser and synchrotron sources.