相关论文: Detection of the Direct Hyperfine Transition of Po…
We report laser-induced-fluorescence spectroscopy of the \({}^{1}S_{0}\rightarrow{}^{3}P_{1}\) intercombination transition in neutral zinc at \(307.6~\mathrm{nm}\). Isotope shifts are measured for all stable isotopes with kHz-level…
Strong coupling between light and matter occurs when the two interact strongly enough to form new hybrid modes called polaritons. Here we report on the strong coupling of both the electric and magnetic degrees of freedom to an ultrafast…
We perform a comparative study of the breakup of positronium and ionization of atomic hydrogen by projectile-nuclei in the weak perturbation collision regime, $Z_p e_0^2/\hbar \ll v < c $ ($v$ is the collision velocity, $Z_p$ the projectile…
The contribution of hadronic scattering of light-by-light to the hyperfine structure of muonium is calculated using experimental data on the transition form factors of two photons into a hadron. The amplitudes of interaction between a muon…
Uncertainty of the theoretical prediction for the hyperfine splitting in the ground state of muonium is considered. It is compared with the respective discussion in the two most recent CODATA adjustments of the fundamental physical…
The differential and total cross sections for electron capture by positrons from helium atoms are calculated using a first-order distorted wave theory satisfying the Coulomb boundary conditions. In this formalism a parametric potential is…
High-energy hadronic reactions with proton-to-neutron transitions (and vice versa) with small momentum transfer allow to study the properties of nearly on-shell pions, which cannot be accessed otherwise. We overview the recent results for…
We investigate the potential of short-baseline experiments in order to measure the dispersion relation of the (muon) neutrino, with a prospect of eventually measuring the neutrino mass. As a byproduct, the experiment would help to constrain…
High intensity back-scattered laser beams will allow the efficient conversion of a substantial fraction of the incident lepton energy into high energy photons, thus significantly extending the physics capabilities of an electron-electron or…
The recent PSI Lamb shift experiment and the controversy about proton size revived the interest in measuring the hyperfine splitting in muonic hydrogen as an alternative possibility for comparing ordinary and muonic hydrogen spectroscopy…
Highly charged ions of heavy actinides from uranium to einsteinium are studied theoretically to find optical transitions sensitive to the variation of the fine structure constant. A number of promising transitions have been found in ions…
In a strong magnetic field, ultra-relativistic electrons or positrons undergo spin flip transitions as they radiate, preferentially spin polarizing in one direction -- the Sokolov-Ternov effect. Here we show that this effect could occur…
In recent years, enhanced light-matter interactions through a plethora of dipole-type polaritonic excitations have been observed in two-dimensional (2D) layered materials. In graphene, electrically tunable and highly confined…
We briefly review the theoretical and experimental results concerning decays of positronium. Possible solutions of the "orthopositronium lifetime puzzle" are discussed. Positronium annihilation into neutrinos is examined and disagreement is…
In-source resonant ionization laser spectroscopy of the even-$A$ polonium isotopes $^{192-210,216,218}$Po has been performed using the $6p^37s$ $^5S_2$ to $6p^37p$ $^5P_2$ ($\lambda=843.38$ nm) transition in the polonium atom (Po-I) at the…
Laser spectroscopy of the low lying $^1$P and $^3$D states in atomic barium has been performed. This work contributes substantially to the development of an effective laser cooling and trapping for heavy alkaline earth elements and aims in…
The absolute frequency measurement for all of the hyperfine transitions of 6P1/2 -> 7S1/2 using a self-referencing frequency comb is reported. This transition can be used as a bench marker for the accurate atomic wave function, and then…
We evaluate the feasibility of using magnetic-dipole (M1) transitions in highly-charged ions as a basis of an optical atomic clockwork of exceptional accuracy. We consider a range of possibilities, including M1 transitions between clock…
The hyperfine structure of the ground state of erbium doped yttrium orthosilicate is analyzed with the use of electron paramagnetic resonance experiments in a tunable microwave resonator. This work was prompted by the disagreement between…
A two-step, two-color laser spectroscopy technique has been used to measure the hyperfine splitting of the 7p$_{1/2}$ excited state in $^{203}$Tl and $^{205}$Tl, as well as the isotope shift within the 7s$_{1/2}$ - 7p$_{1/2}$ transition.…