Unveiling Ultrafast-Weak-Field Coherent Control of Indirect Dissociation Reactions.

Coherent control of molecular photodissociation through one-photon transitions has become a topic of interest in physical chemistry. Previous studies have shown that modulating the spectral phase of a single ultrafast laser pulse while keeping its spectral amplitude constant does not affect the dissociation yield of reactions originating from a pure eigenstate of the ground electronic state. Here, we explore the indirect photodissociation reaction of NaI molecules using theoretical and numerical methods.

Valence band dispersion measurements of perovskite single crystals using angle-resolved photoemission spectroscopy.

The electronic structure of a cleaved perovskite (CHNHPbBr) single crystal was studied in an ultra-high vacuum (UHV) system using angle-resolved photoemission spectroscopy (ARPES) and inverse photoelectron spectroscopy (IPES). Highly reproducible dispersive features of the valence bands were observed with symmetry about the Brillouin zone center and boundaries. The largest dispersion width was found to be ∼0.

Imaging the three-dimensional Fermi-surface pairing near the hidden-order transition in URu2Si2 using angle-resolved photoemission spectroscopy.

We report angle-resolved photoemission spectroscopy experiments probing deep into the hidden-order state of URu(2)Si(2), utilizing tunable photon energies with sufficient energy and momentum resolution to detect the near Fermi-surface (FS) behavior. Our results reveal (i) the full itinerancy of the 5f electrons, (ii) the crucial three-dimensional k-space nature of the FS and its critical nesting vectors, in good comparison with density-functional theory calculations, and (iii) the existence of hot-spot lines and pairing of states at the FS, leading to FS gapping in the hidden-order phase.