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Abstract Our recent study Aiswarya (2024Phys. Rev. Lett.133033002) accessed the angle-energy two-dimensional diffraction in elastic electron scattering from C₆₀with implications for ultrafast electron diffraction studies. The objective of the current investigation is to carry out a detailed characterization of the Fourier transformed signals of diffraction fringes in the angular distribution for a range of impact energies. Results shed light on how the electron’s perception of the molecular target evolves as a function of its de Broglie wavelength and tends to be geometrically accurate at faster impacts. For very fast impacts and the resulting dominance of high angular momentum partial waves, the target becomes partly hidden within a spherical shell of repulsive centrifugal barrier, from which the electron ‘self-diffracts’. This effect is favored by the polarization interaction of C₆₀. Potentials from a jellium-based density functional theory within the local density approximation and an annular square well model are independently applied to simulate the C₆₀environment. Results from the partial wave analysis and Born approximation are independently analyzed by a fast Fourier transformation technique. 

NThe Fraunhofer diffraction of quantum particles from materials with sharp electron-density edges or symmetric bond structures is ubiquitous. In contrast, diffraction from atoms with a characteristic asymptotically diffused electron distribution is far less intuitive, although known for many years. The current study unravels an unusual diffraction mechanism of elastic electrons from diffused atomic diffractors. Consequently, the fringe pattern converted to the Fourier reciprocal space maps out the effective scattering potential, which is not accessible in direct measurements. This may benefit large-volume and multiscale computational modeling of processes in materials where adopting the complex exact potentials is challenging and expensive. The study employs a relativistic partial-wave analysis with atoms modeled in the Dirac-Fock formalism and performs e-Cd measurements in absolute scale. Analysis for Mg, Ba, and Ra targets demonstrates the universality of the mechanism.ot Available 

We study the ground state structure and aspects of photoionization dynamics of the Na20@C240 endofullerene. The structure shows effects from the electronic coupling between the nested cluster and the fullerene cage. They include the (i) alterations of the overall potential, and thus, the force field, (ii) electron transfer from the cluster to the fullerene forming ionic units, and (iii) hybridization from the admixture of free Na20 occupied levels with experimentally known super-atom molecular orbital (SAMO) type empty levels of C240 accessible in the jellium-density functional theory model. These modifications influence the photoionization dynamics of the endofullerene. For the high energy ionization of Na20-type levels, a significant overall enhancement of the cross section is noted from additional ionizing force that C240 offers. More remarkably, the photoexcited plasmons, both the giant plasmon and the higher energy plasmon, in C240 decay in parts through Na20 ionization continuum via the resonant intercluster Coulombic decay (ICD) process. These lead to dramatic enhancements in the ionization of individual Na20-type levels, resulting in enhancements in the cluster’s total ionization yield. Based on hybridization, this enhancement incorporates a coherent mixing of the ICD and SAMO-induced Auger-decay amplitude, in which the ICD contribution is dominant. 

Atomic, molecular, and optical (AMO) physics is a vastly important sub-discipline [...] 

Access to time delay in a projectile-target scattering is a fundamental tool in understanding their interactions by probing the temporal domain. The present study focuses on computing and analyzing the Eisenbud-Wigner-Smith (EWS) time delay in low energy elastic e−C60 scattering. The investigation is carried out in the framework of a non-relativistic partial wave analysis (PWA) technique. The projectile-target interaction is described in (i) Density Functional Theory (DFT) and (ii) Annular Square Well (ASW) static model, and their final results are compared in details. The impact of polarization on resonant and non-resonant time delay is also investigated. 

The ground state and photoionization properties of Nax (x = 20, 40, and 92) clusters are investigated using a method based on density functional theory (DFT) in a spherical jellium frame. Two different exchange–correlation treatments with the Gunnarsson–Lundqvist parametrization are used: (i) the electron self-interaction correction (SIC) scheme and (ii) the van Leeuwen–Baerends (LB94) scheme based on the gradient of the electron density. The shapes of the mean-field potentials and bound state properties, obtained in the two schemes, qualitatively agree, but differ in the details. The effect of the schemes on the photoionization dynamics, calculated in linear response time-dependent DFT is compared, in which the broader features are found to be universal. The general similarity of the results in SIC and LB94 demonstrates the reliability of DFT treatments. The study further elucidates the evolution of the ground state and ionization description as a function of the cluster size. 

Extreme light confinement in plasmonic nanosystems enables novel applications in photonics, sensor technology, energy harvesting, biology, and quantum information processing. Fullerenes represent an extreme case for nanoplasmonics: They are subnanometer carbon-based molecules showing high-energy and ultrabroad plasmon resonances; however, the fundamental mechanisms driving the plasmonic response and the corresponding collective electron dynamics are still elusive. Here, we uncover the dominant role of electron correlations in the dynamics of the giant plasmon resonance (GPR) of the subnanometer system C₆₀by using attosecond photoemission chronoscopy. We find a characteristic photoemission delay of up to about 300 attoseconds that is purely induced by coherent large-scale electron correlations in the plasmonic potential. These results provide insights into the nature of the plasmon resonances in subnanometer systems and open perspectives for advancing nanoplasmonic applications.