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The work presents the possibilities for using the ML/DL/HPC ecosystem deployed on the HybriLIT Heterogeneous Platform (Meshcheryakov Laboratory of Information Technologies JINR) on top of JupyterHub, which provides opportunities for solving tasks not only in the field of machine learning and deep learning, but also for the convenient organization of calculations and scientific visualization. The ecosystem allows one to develop and implement program modules in Python, as well as to carry out methodical computations. The relevance of deploying such an environment is primarily associated with the great demand for software modules that are provided to a group of researchers or the scientific community, when all stages of the study can be reproduced; the code has been modified and used by the scientific community. Using the example of solving a specific problem to study the dynamics of magnetization in a Phi-0 Josephson Junction (Superconductor-Ferromagnet-Superconductor structure), a methodology for developing software modules is presented; it enables not only to carry out calculations, but also to visualize the results of the study and accompany them with the necessary formulas and explanations. The possibility of parallel implementation of the algorithm for performing computations for various values of parameters of the model based on the Joblib Python library is shown, and the results of computational experiments demonstrating the efficiency of parallel data processing are presented.

Examination of an annular system of underdamped Josephson junctions in the presence of external radiation showed that the ability of the system to lock with some external radiation was determined not only by the number but also by the type of rotating excitations (fluxons or antifluxons). Shapiro steps can be observed in the current-voltage characteristic only in the system with trapped fluxons or in the system with fluxon-antifluxon pairs. If the trapped fluxons circulate simultaneously with fluxon-antifluxon pairs, there are no Shapiro steps regardless of the amplitude or frequency of the applied external radiation. © 2020 American Physical Society.

The appearance and origin of resonance phenomena are studied in an annular system of underdamped Josephson junctions. If no fluxon is trapped in the system, the dynamics is governed by the motion of fluxon-antifluxon pairs. If, on the other hand, trapped fluxons are present, in addition to their motion, the system can also exhibit the simultaneous motion of trapped fluxons and fluxon-antifluxon pairs. Locking between the rotating excitations (fluxons and antifluxons) and the Josephson frequency leads to the appearance of zero-field steps in the current-voltage characteristics, whose number is determined by the number of junctions and the total number of excitations present in the system. The obtained results clearly show that the branching of zero-field steps due to resonance between the rotating excitations and plasma oscillations in their tails appears only at the lower steps and completely disappears at the higher steps. A comparative analysis between systems without and those with trapped fluxons shows a correlation between their current-voltage characteristics. From a high-resolution analysis some special features of zero-field steps emerge such as an additional branch due to resonance between the pulsating fluxon and the Josephson frequency. Examination of systems with the same number but different types of excitations further reveals that their dynamics is determined not only by the number, but also by the type of excitations, i.e., systems with the same number but different types of excitations have different current-voltage characteristics. © 2020 American Physical Society.