Vector-resonance-multimode instability

The modulation and multimode instabilities are the main mechanisms which drive spontaneous spatial and temporal patterns formation in a vast number of nonlinear systems ranging from biology to the laser physics. Using Er-doped fiber laser as a test bed, here for the first time we demonstrate both experimentally and theoretically a new type of a low threshold vector resonance multimode instability which inherits features of multimode and modulation instabilities. The same as for the multimode instability, the large number of longitudinal modes can be excited without modes synchronization. To enable modulation instability, we modulate the state of polarization of the lasing signal with the period of the beat length by adjustment of the in-cavity birefringence and the state of polarization of the pump wave. As a result, we show regimes tunability from complex oscillatory to periodic with longitudinal modes synchronization in the case of the resonance matching between beat and cavity lengths. Apart from the interest in laser physics for unlocking tunability and stability of dynamic regimes, the proposed mechanism of the vector resonance multimode instability can be of fundamental interest for nonlinear dynamics of various distributed systems

Slow deterministic vector rogue waves

For an erbium-doped fiber laser mode-locked by carbon nanotubes, we demonstrate experimentally and theoretically a new type of the vector rogue waves emerging as a result of the chaotic evolution of the trajectories between two orthogonal states of polarization on the Poincare sphere. In terms of fluctuation induced phenomena, by tuning polarization controller for the pump wave and in-cavity polarization controller, we are able to control the Kramers time, i.e. the residence time of the trajectory in vicinity of each orthogonal state of polarization, and so can cause the rare events satisfying rogue wave criteria and having the form of transitions from the state with the long residence time to the state with a short residence time

The study of charged particles kinetics in the electrodes system forming a high-voltage gas discharge

Получено уравнение напряженности неоднородного электростатического поля источника низкотемпературной внеэлектродной плазмы. Представлена модель для расчета траектории движения положительных ионов и электронов, формирующихся за счет зажигания высоковольтного газового разряда в системе электродов, создающих неоднородное электростатическое поле с высоким градиентом напряженности. Были построены теоретические кривые указанных траекторий движения и получено хорошее согласие результатов моделирования с экспериментальными данными. The equation for the strength of a non-uniform electrostatic field of low-temperature non-electrode plasma source is obtained. A model is presented for calculating the trajectory of positive ions and electrons motion formed due to the ignition of a high-voltage gas discharge in a electrodes system that create a non-uniform electrostatic field with a high gradient of field strength. The theoretical curves of the specified trajectories of motion were constructed and good agreement between the simulation results and experimental data was obtained.Работа выполнена при поддержке гранта Российского научного фонда №19-19-00020

Contemporary basic oxygen steelmaking in the USSR and the outlook for its future development

Translated from Russian (Stal' 1986 (10) p. 1-4)SIGLEAvailable from British Library Document Supply Centre- DSC:5828.4(M--37158)T / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Contemporary basic oxygen steelmaking in the USSR and the outlook for its future development

Translated from Russian (Stal' 1986 (10) p. 1-4)SIGLEAvailable from British Library Document Supply Centre- DSC:5828.4(M--37158)T / BLDSC - British Library Document Supply CentreGBUnited Kingdo