Calculation of Probability Density Distribution of Ultracold Atoms and Molecules in Waveguide-Like Traps

The quantitative description of the confined quantum scattering in waveguide-like atomic traps is an actual problem of modern physics of ultracold atoms and molecules. It is a challenging problem of computational mathematics to integrate the few-dimensional Schrödinger equation describing such scattering. In the present work we show how the split-operator method developed by V.S. Melezhik in discrete-variable representation can be parallelized and extended for calculation of probability density distribution in such quantum systems. By using as an example the confined collision of Li atoms with Yb ions in a hybrid atom-ion trap we demonstrate calculation of the time-evolution of the atom-ion probability density distribution. The calculated function is an important parameter for analysis of this reaction. Due to resent development of unique experimental technique in this field it becomes actual experimental analysis of cold low-dimensional few-body systems. However, interpretation and planning of the experiments demand quantitative description of the systems. The present work opens promising perspective in the development of this direction. © 2019, Springer Nature Switzerland AG

Quantum-semiclassical calculation of transition probabilities in antiproton collisions with helium ions

We have developed a quantum-semiclassical approach for calculation of transition probabilities in few-dimensional quantum systems. In this approach the problem is reduced to the Schrödinger-like equation for some degrees of freedom which integrated symphoniously with the classical equations describing the remaining part. This approach was successfully applied for treating self-ionization of hydrogen-like ions in magnetic fields, break-up of some halo nuclei and for excitation and stripping of helium ions by protons. Here we present the method application to calculation of ionization and excitation/deexcitation of helium ions by slow antiprotons. The calculated cross sections are important for experimental investigations in antiproton physics. Moreover, the considered case is very perspective as an object for investigation of quantum measurements. Actually, the charge-exchange channel, dominant in collisions with protons, is absent in our case and all possible quantum communication channels are accurately described in our approach. © 2017, Springer International Publishing AG

Quantum-semiclassical calculation of transition probabilities in antiproton collisions with helium ions

We have developed a quantum-semiclassical approach for calculation of transition probabilities in few-dimensional quantum systems. In this approach the problem is reduced to the Schrödinger-like equation for some degrees of freedom which integrated symphoniously with the classical equations describing the remaining part. This approach was successfully applied for treating self-ionization of hydrogen-like ions in magnetic fields, break-up of some halo nuclei and for excitation and stripping of helium ions by protons. Here we present the method application to calculation of ionization and excitation/deexcitation of helium ions by slow antiprotons. The calculated cross sections are important for experimental investigations in antiproton physics. Moreover, the considered case is very perspective as an object for investigation of quantum measurements. Actually, the charge-exchange channel, dominant in collisions with protons, is absent in our case and all possible quantum communication channels are accurately described in our approach. © 2017, Springer International Publishing AG