Soliton dynamics at an interface between uniform medium and nonlinear optical lattice

We study trapping and propagation of a matter-wave soliton through the interface between uniform medium and a nonlinear optical lattice (NOL). Different regimes for transmission of a broad and a narrow soliton are investigated. Reflections and transmissions of solitons are predicted as function of the lattice phase. The existence of a threshold in the amplitude of the nonlinear optical lattice, separating the transmission and reflection regimes, is verified. The localized nonlinear surface state, corresponding to the soliton trapped by the interface, is found. Variational approach predictions are confirmed by numerical simulations for the original Gross-Pitaevskii equation with nonlinear periodic potentials

Collective excitations of BEC under anharmonic trap position jittering

Collective excitations of a Bose-Einstein condensate under periodic oscillations of a quadratic plus quartic trap position has been studied. A coupled set of variational equations is derived for the width and the condensate wave function center. Analytical expressions for the growth of oscillation amplitudes in the resonance case are derived. It is shown that jittering of an anharmonic trap position can cause double resonance of the BEC width and the center of mass oscillation in the wide range of the BEC parameters values. The predictions of variational approach are confirmed by full numerical simulations of the 1D GP equation.Comment: This paper contains a manuscript - SolAnJPB.tex and figures (fig1 - fig1a.eps and fig1b.eps, fig2 - fig2.eps, fig3 - fig3a.eps and fig3b.eps, fig4 - fig4a.eps and fig4b.eps). The manuscript has been prepared using LATEX2e with the iopart class and the figures in encapsulated PostScrip

Effects of quantum fluctuations on macroscopic quantum tunneling and self-trapping of BEC in a double well trap

We study the influence of quantum fluctuations on the macroscopic quantum tunneling and self-trapping of a two-component Bose-Einstein condensate in a double-well trap. Quantum fluctuations are described by the Lee-Huang-Yang term in the modified Gross-Pitaevskii equation. Employing the modified Gross-Pitaevskii equation in scalar approximation, we derive the dimer model using a two-mode approximation. The frequencies of Josephson oscillations and self-trapping conditions under quantum fluctuations are found analytically and proven by numerical simulations of the modified Gross-Pitaevskii equation. The tunneling and localization phenomena are investigated also for the case of the Lee-Huang-Yang fluid loaded in the double-well potential.Comment: 14 pages, 9 figure

Intoxication syndrome in patients with pulmonary tuberculosis in relation to the system glutathione transferase gene polymorphism

In 178 patients with different clinical forms of pulmonary tuberculosis carried out pharmacogenetic testing to determine gene polymorphism glutathione S-transferase system (GSTM1, GSTT1). Estimated the severity and duration of clinical manifestations of the syndrome of intoxication, depending on the gene polymorphism of glutathione S-transferase system (GSTM1, GSTT1). It was found that the combination of “zero” to develop genotypes GSTM1 and GSTT1 enzyme is a predictor of the severity and duration of symptoms of intoxication persisting

Resonances in a trapped 3D Bose-Einstein condensate under periodically varying atomic scattering length

Nonlinear oscillations of a 3D radial symmetric Bose-Einstein condensate under periodic variation in time of the atomic scattering length have been studied analytically and numerically. The time-dependent variational approach is used for the analysis of the characteristics of nonlinear resonances in the oscillations of the condensate. The bistability in oscillations of the BEC width is invistigated. The dependence of the BEC collapse threshold on the drive amplitude and parameters of the condensate and trap is found. Predictions of the theory are confirmed by numerical simulations of the full Gross-Pitaevski equation.Comment: 17 pages, 10 figures, submitted to Journal of Physics

Dynamics of bright matter wave solitons in a quasi 1D Bose-Einstein condensate with a rapidly varying trap

The dynamics of a bright matter wave soliton in a quasi 1D Bose-Einstein condensate with periodically rapidly varying trap is considered. The governing equation is derived based on averaging over fast modulations of the Gross-Pitaevskii (GP) equation. This equation has the form of GP equation with effective potential of more complicated structure than unperturbed trap. For the case of inverted (expulsive) quadratic trap corresponding to unstable GP equation, the effective potential can be stable. For the bounded in space trap potential it is showed that the bifurcation exists, i.e.,the single well potential bifurcates to the triple well effective potential. Stabilization of BEC cloud on-site state in the temporary modulated optical lattice is found. (analogous to the Kapitza stabilization of the pendulum). The predictions of the averaged GP equation are confirmed by the numerical simulations of GP equation with rapid perturbations.Comment: 15 pages, 4 figure

Collective oscillations of a quasi one dimensional Bose condensate under damping

Influence of the damping on collective oscillations of a one-dimensional trapped Bose gas in the mean field regime has been studied. Using the phenomenological damping approach developed by L.P. Pitaevskii, modified variational equations for the parameters of the condensate wave function is derived. Analytical expressions for the condensate parameters in equilibrium state have been obtained. Bistability in nonlinear oscillations of the condensate under periodic variations of the trap potential is predicted. The predictions of the modified variational approach are confirmed by full numerical simulations of the 1D GP equation with the damping.Comment: It contains a manuscript - damp1DBC.tex and figures (fig1a - fig1a.eps, fig1b - fig1b.eps, fig2 - fig2.eps, fig3 - fig3.eps and fig4 - fig4.eps

СИНДРОМ ИНТОКСИКАЦИИ У БОЛЬНЫХ ТУБЕРКУЛЕЗОМ ЛЕГКИХ В ЗАВИСИМОСТИ ОТ ПОЛИМОРФИЗМА ГЕНОВ СИСТЕМЫ ГЛУТАТИОНТРАНСФЕРАЗ

In 178 patients with different clinical forms of pulmonary tuberculosis carried out pharmacogenetic testing to determine gene polymorphism glutathione S-transferase system (GSTM1, GSTT1). Estimated the severity and duration of clinical manifestations of the syndrome of intoxication, depending on the gene polymorphism of glutathione S-transferase system (GSTM1, GSTT1). It was found that the combination of “zero” to develop genotypes GSTM1 and GSTT1 enzyme is a predictor of the severity and duration of symptoms of intoxication persisting.У 178 пациентов с различными клиническими формами туберкулеза легких выполнено фармакогенетическое тестирование для определения полиморфизма генов системы глутатионтрансфераз (GSTM1, GSTT1). Оценена выраженность и длительность клинических проявлений синдрома интоксикации в зависимости от полиморфизма генов системы глутатионтрансфераз (GSTM1, GSTT1). Установлено, что комбинация «нулевых» генотипов по выработке ферментов GSTM1 и GSTT1 является предиктором выраженных и длительно сохраняющихся симптомов интоксикации