Atomic Physics
When three particles in three dimensions interact with a short-range potential fine-tuned to an infinite scattering length, they form an infinite sequence of loosely bound states obeying discrete scale invariance known as Efimov states.…
Ab initio calculation of low energy scattering of electrons (muons) off hydrogen (muonic hydrogen) are performed on the basis of Faddeev-Merkuriev (FM) equations. The explicit contribution of induced dipole interaction in the asymptotic…
We present tabulated data for numerical calculations of relative para- and diamagentic contributions to the magnetic shielding constant ($\sigma$) of the Dirac one-electron atoms with a pointlike, spinless and motionless nuclei of charge…
We study the nonlinear optical response of argon to a four-wave-mixing pulse sequence consisting of an extreme ultraviolet pulse, an overlapping collinear IR and an non-collinear delayed IR pulses. Absorption of an extreme ultraviolet and…
The relativistic corrections for the Dirac-Coulomb system are derived through the method of non-relativistic expansion. By expanding the large and small components of the Dirac wave function and the energy eigenvalues in terms of the square…
In low-energy collisions between two dipolar molecules, the long-range dipole-dipole interaction plays an important role in the scattering dynamics. Merged beam configurations offer the lowest collision energies achievable, but they…
We present a comprehensive study of the angular distribution of photons emitted during the resonant two-photon electron capture by H-like uranium ions. Focusing on the energies of incident electrons, at which the dielectronic recombination…
Laser cooling methods for trapped ions are most commonly studied at low energies, i.e., in the Lamb-Dicke regime. However, ions in experiments are often excited to higher energies for which the Lamb-Dicke approximation breaks down. Here we…
We have measured the geopotential difference between two locations separated by $457~\mathrm{km}$ by comparison of two optical lattice clocks via an interferometric fiber link, utilizing the gravitational redshift of the clock transition…
We have measured the spontaneous and photo-induced decays of anionic gold clusters, Au$_N^-$, with sizes ranging from $N = 2$ to 13, and 15. After production in a sputter ion source, the size-selected clusters were stored in the cryogenic…
We explore the process of orbital angular momentum (OAM) transfer from a twisted light beam to an electron in atomic ionization within the first Born approximation. The characteristics of the ejected electron are studied regardless of the…
The effective control of atomic coherence with cold atoms has made atom interferometry an essential tool for quantum sensors and precision measurements. The performance of these interferometers is closely related to the operation of large…
We report on precision spectroscopy of the 6s$^2$ $^1$S$_0\to$6s6p $^3$P$_1$ intercombination line of mercury in the deep ultraviolet, by means of a frequency-comb referenced, wavelength-modulated, saturated absorption technique. This…
We are developing a single-ion optical clock based on a surface-electrode (SE) trap that we will operate with $^{171}$Yb$^+$ ions on the electric quadrupole transition at 435.5 nm. We present heating rate measurements performed with a…
The molecular anion C$_2^-$ has been of interest in the last few years as a candidate for laser cooling due to its electronic structure and favourable branching ratios to the ground electronic and vibrational state. Molecular hydrogen has…
It has been shown by Fano (1969) https://doi.org/10.1103/PhysRev.178.131 that photoionization of a c{\ae}sium atom by a laser pulse tuned to the vicinity of a Cooper minimum generates spin-polarized electrons. Here we show that while…
Electronically excited atoms or molecules may deexcite by emission of a secondary electron through an Auger-Meitner decay. This deexcitation process is typically considered to be exponential in time. This is strictly speaking, however, only…
The elastic scattering of spinless vortex electrons on realistic target atoms has been investigated. In particular, expressions are derived in different approximations for the elastic angular-differential cross sections. We develop a…
Despite their importance in a wide variety of applications, the estimation of ionization cross sections for large molecules continues to present challenges for both experiment and theory. Machine learning algorithms have been shown to be an…
In traditional scattering theory, the incident projectile is assumed to have an infinite coherence length. However, over the last decade, experimental and theoretical studies of collisions using heavy ion projectiles have shown that this…