原子物理
Cold collisions between two Rydberg rubidium atoms ($^{87}$Rb) are investigated by controlling the impact parameter and collision energy. Optical tweezers are employed to hold one atom stationary while propelling the other to a constant…
Precise evaluation of the isotope shift (IS) factors for seven low-lying potassium (K) states is achieved using relativistic coupled-cluster (RCC) theory. The energies of these states are assessed and compared with experimental data to…
In this work, we investigate the ionization of silicon by electron impacts in hot plasmas. Our calculations of the cross sections and rates rely on the Coulomb-Born-Exchange, Binary-Encounter-Dipole and Distorted-Wave methods implemented in…
The complete second-order hyperfine-interaction correction is calculated for centroid energy levels of H, D, and $^3$He atoms. For $^3$He, the corrections of $-2.075$~kHz and $-0.305$~kHz beyond the leading hyperfine-mixing contribution are…
We study a resonant interaction of an elliptically polarized light wave with $^{87}$Rb vapor (D$_1$ line) exposed to a transverse magnetic field. A $5$$\times$$5$$\times$$5$~mm$^3$ glass vapor cell is used for the experiments. The wave…
Using a quantum-mechanical close-coupling method, we calculate cross sections for fine structure excitation and relaxation of Si and S atoms in collisions with atomic hydrogen. Rate coefficients are calculated over a range of temperatures…
Fine-structure transitions can be involved in various processes including photon absorption, charge transfer and inelastic collision between ions, electrons and neutral atoms. We present fine-structure excitation and relaxation cross…
We make absolute frequency measurements of Cs Rydberg transitions, $\vert 6S_{1/2}, F=3 \rangle \rightarrow \vert nS_{1/2}~(n=23\rm{-}90)\rangle$ and $\vert nD_{3/2,5/2}~(n=21\rm{-}90)\rangle$, with an accuracy of less than $ 72\,\rm kHz$.…
High-accuracy Multi-Configuration Dirac-Hartree-Fock with Configuration Interaction calculations of level energies and transition rates have been carried out for iodine $I^{8+}$ through $I^{12+}$ ions related to the [Kr]4d$^n$ ($n$ = 5-9)…
The rich information of electron energy-loss spectroscopy (EELS) comes from the complex inelastic scattering process whereby fast electrons transfer energy and momentum to atoms, exciting bound electrons from their ground states to higher…
In molecular beam scattering experiments, an important technique for measuring product energy and angular distributions is velocity map imaging following photoionization. For studies with cold molecular beams, the resolution is often…
Fourier transform spectra of Nd Penning and hollow cathode discharge lamps were recorded within the region 32,500-54,000 cm$^{-1}$ (3077-1852 {\AA}) and grating spectra of Nd vacuum sliding sparks were recorded within the regions 820-1159…
In this study, we investigated Rydberg atom-based microwave electrometry using polarization spectroscopy in a room-temperature vapor cell. By measuring Autler-Townes splitting in the electromagnetically induced transparency (EIT) spectrum,…
We investigate magneto-optical trap loss spectroscopy of Rydberg excited $^{85}$Rb ($66\leq n \leq 68~S_{1/2}$) atoms, placed inside a tailored microwave cavity. The cavity frequency at 13.053 GHz is in resonance with the $67S_{1/2}…
Efficient sub-Doppler laser cooling and optical trapping of YO molecules offer new opportunities to study collisional dynamics in the quantum regime. Confined in a crossed optical dipole trap, we achieve the highest phase-space density of…
When three particles in three dimensions interact with a short-range potential fine-tuned to an infinite scattering length, they form an infinite sequence of loosely bound states obeying discrete scale invariance known as Efimov states.…
Ab initio calculation of low energy scattering of electrons (muons) off hydrogen (muonic hydrogen) are performed on the basis of Faddeev-Merkuriev (FM) equations. The explicit contribution of induced dipole interaction in the asymptotic…
We present tabulated data for numerical calculations of relative para- and diamagentic contributions to the magnetic shielding constant ($\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…