V. B. Ternovsky

Spectroscopy of Radiative Decay Processes in Heavy Rydberg Alkali Atomic Systems

We present the results of studying the radiation decay processes and computing the probabilities and oscillator strengths of radiative transitions in spectra of heavy Rydberg alkali-metal atoms. All calculations of the radiative decay (transitions) probabilities have been carried out within the generalized relativistic energy approach (which is based on the Gell-Mann and Low S-matrix formalism) and the relativistic many-body perturbation theory with using the optimized one-quasiparticle representation and an accurate accounting for the critically important exchange-correlation effects as the perturbation theory second and higher orders ones. The precise data on spectroscopic parameters (energies, reduced dipole transition matrix elements, amplitude transitions) of the radiative transitions nS1/2→n′P1/2,3/2 (n = 5, 6; n′ = 10–70), nP1/2,3.2→n′D3/2,5/2 (n = 5, 6; n′ = 10–80) in the Rydberg Rb, Cs spectra and the transitions 7S1/2-nP1/2,3/2, 7P1/2,3.2-nD3/2,5/2 (n = 20–80) in the Rydberg francium spectrum are presented. The obtained results are analyzed and discussed from viewpoint of the correct accounting for the relativistic and exchange-correlation effects. It has been shown that theoretical approach used provides an effective accounting of the multielectron exchange-correlation effects, including effect of essentially non-Coulomb grouping of Rydberg levels and others.

Non-Linear Chaotic Dynamics of Quantum Systems: Molecules in an Electromagnetic Field and Laser Systems

We present a general, uniform chaos-geometric formalism to analysis, modelling and forecasting a non-linear chaotic dynamics of quantum systems (such as diatomic molecules in an electromagnetic infrared field, laser and quantum generators system etc.). The approach is based on using quantum-mechanical and kinetical models for quantum and laser systems combined with the advanced techniques such as a multi-fractal method, mutual information approach, correlation integral and false nearest neighbour algorithms, the Lyapunov exponent’s (LE) analysis, and surrogate data method, prediction models etc. The results of the numerical studying a chaotic dynamics of diatomic molecules (on example of the GeO molecule in an infrared field) and some laser systems are listed. There are presented data on the topological and dynamical invariants, in particular, the correlation, embedding, Kaplan-Yorke dimensions, LE, Kolmogorov’s entropy etc.

Relativistic Many-Body Perturbation Theory Calculations of the Hyperfine Structure and Oscillator Strength Parameters for Some Heavy Element Atoms and Ions

The formalism of the relativistic many-body perturbation theory with an optimized zeroth approximation is applied to computing the energies and hyperfine structure constants for some heavy Li-like multicharged ions and alkali (caesium) atoms. The exchange-correlation, nuclear and radiative corrections are correctly and effectively taken into account. The modified Uehling-Serber approximation is used to take into account for the Lamb shift polarization part. In order to take into account the contribution of the Lamb shift self-energy part we have used the generalized non-perturbative procedure, developed by Ivanov-Ivanova et al. The energies and oscillator strengths of radiation transition in spectra of some Li-like ions (Z = 20 – 70) and Cs are computed on the basis of the combined relativistic energy approach (S-matrix formalism) and relativistic many-body perturbation theory. The data on oscillator strengths of radiative transitions from the ground state to the low-excited and Rydberg states 2s1/2 – np1/2,3/2, np1/2,3/2-nd3/2,5/2 (n = 2 – 12) in the Li-like ions are presented. Some results are obtained at first. It is performed an analysis of the computed oscillator strength values with available theoretical and experimental results.

Nonlinear dynamics of laser systems with elements of a chaos: Advanced computational code

A general, uniform chaos-geometric computational approach to analysis, modelling and prediction of the non-linear dynamics of quantum and laser systems (laser and quantum generators system etc) with elements of the deterministic chaos is briefly presented. The approach is based on using the advanced generalized techniques such as the wavelet analysis, multi-fractal formalism, mutual information approach, correlation integral analysis, false nearest neighbour algorithm, the Lyapunovs exponents analysis, and surrogate data method, prediction models etc There are firstly presented the numerical data on the topological and dynamical invariants (in particular, the correlation, embedding, Kaplan-York dimensions, the Lyapunovs exponents, Kolmogorovs entropy and other parameters) for laser system (the semiconductor GaAs/GaAlAs laser with a retarded feedback) dynamics in a chaotic and hyperchaotic regimes.