Vortex ultrasonic beams
Vortex ultrasonic beams
M.E. Terzi, P.V. Yuldashev, O.A. Sapozhnikov
Vortex beams are waves those are able to give torque to a small obstacle. In this research in order to create a vortex beam the special phase screen is used. Such screen turns originally plane wave in helical. The experiment is conducted and modeling in the program MATLAB is made.
Show AbstractDegradation and spectral-spatial characteristics of the radiation of high-power injection lasers
Degradation and spectral-spatial characteristics of the radiation of high-power injection lasers
V.V. Bliznyuk$^1$, M.A. Britt$^1$, I.S. Gadaev$^1$, O.I. Koval$^1$, A.G. Rzhanov$^2$, G.A. Solovyev$^1$, A.A. Starodumov$^2$
In this work it has been experimentally and theoretically investigated the relationship between the slow degradation of high-power semiconductor injection lasers with quantum well (InGaAs/InGaAsP) and their spectra, radiation pattern and polarization of the radiation. For the theoretical description of the phenomena we use an independent channels model for generating radiation.
Show AbstractHigh-order harmonic generation and Fano resonances
High-order harmonic generation and Fano resonances
M.A. Khokhlova$^{1,2}$ , V.V. Strelkov$^{2,3}$
We suggest the theory describing generation of a harmonic resonant with the transition from ground to autoionizing state of the generating particle. Calculating both harmonic amplitudes and phases, we study the attopulse generation using these harmonics.
Show AbstractGeneration of higher harmonics in the gap modification graphene in the presence of static and alternating electric fields
Generation of higher harmonics in the gap modification graphene in the presence of static and alternating electric fields
P.V. Badicova, S.Yu. Glazov
We have studied the response of the graphene with a gap to external dc and ac electric fields without using of low-energy approximation for the energy carrier that allows us to study the effects of a broader range of parameters of applied electric fields. The electronic system of graphene described by Boltzmann's kinetic equation in the constant relaxation-time approximation. The amplitude of the higher harmonics on the characteristics of applied fields is studied.
Show AbstractThe influence of the signal filtration on the characteristics of intermittent behavior in the system of unidirectionally coupled tunnel diode generators
The influence of the signal filtration on the characteristics of intermittent behavior in the system of unidirectionally coupled tunnel diode generators
M.O. Zhuravlev$^{1,2}$, A.O. Selskii$^{1,2}$, A.A. Koronovskii$^{1,2}$, O.I. Moskalenko$^{1,2}$, A.E. Hramov$^{1,2}$
The intermittent behavior that can occur in the chaotic systems with the signal filtration near the boundary of the phase chaotic synchronization regime onset is studied. In the framework of the researches carried out we have found that in the system of unidirectionally coupled generators on the tunnel diode the eyelet and ring intermittencies are possible to exist simultaneously near the boundary of the phase chaotic synchronization with the use of the filter with certain parameters.
Show AbstractEffect of the guiding magnetic field on radiation of multi-wave Cherenkov oscillator
Effect of the guiding magnetic field on radiation of multi-wave Cherenkov oscillator
V.A. Cherepenin, V.N. Kornienko
Methods of computer simulation were used for investigating of the effect of the guiding magnetic field on the characteristics of the radiation pulse of the multi-wave Cerenkov generator. It is shown that the dependence of the maximum radiation power of the value of the magnetic field is resonant.
Show AbstractEffect of focusing magnetic field on the interaction between the relativistic electron beam and the microwave field in relativistic overmoded periodic waveguide-based generator
Effect of focusing magnetic field on the interaction between the relativistic electron beam and the microwave field in relativistic overmoded periodic waveguide-based generator
A.I. Slepkov, O.V. Gallyamova, A.I. Schelkonogov
The results of numerical simulation of the interaction between the relativistic electron beam focused by constant magnetic field and the field of an axisymmetric overmoded periodic waveguide are reported. Cyclotron resonant signal amplification and cyclotron absorbtion ranges were revealed, the dynamics of beam electrons was studied, as well as the role of beam parameters that affect the cyclotron resonance.
Show AbstractInteraction of a probe optical signal with quasi-periodic sequence powerful pumping pulses
Interaction of a probe optical signal with quasi-periodic sequence powerful pumping pulses
T.A. Voytova$^1$ , A.V. Yulin$^1$, A.P. Sukhorukov$^2$
The interaction of a short optical pulse with refractive index lattice induced in the nonlinear medium by the pulsed quasi-periodic structures at similar frequencies is considered. The results of numerical simulation of reflection, transmission, multiplexing signal pulse into several sub-pulses for different induced gratings are presented.
Show AbstractPeriod-doubling bifurcation in semiconductor superlattice under the influence of the titled magnetic field
Period-doubling bifurcation in semiconductor superlattice under the influence of the titled magnetic field
А.G. Balanov$^2$, А.А. Koronovskii$^{1,3}$, О.I. Moskalenko$^{1,3}$, А.О. Selskii$^{1,3}$, А.Е. Hramov$^{1,3}$
The semiconductor superlattice is the composite nanostructure used for the generation and the control of the high-frequency oscillations. At present time, attention of the researchers is attracted to the nonlinear dynamics of the electron domains at present nanostructures. In this paper the period-doubling bifurcation phenomena in the semiconductor superlattice under the influence of the titled magnetic field for different temperatures is described.
Show AbstractMethod of optical registration of acoustic field in liquids
Method of optical registration of acoustic field in liquids
L.I. Gilfanova$^{1}$ , S.A. Tsysar$^1$ , P.V. Yuldashev$^1$, V.D. Svet$^2$
The main aim is to develop a method for calculating the structure of the wave field in a heterogeneous medium of skull bone. Phantoms of cranial bones were created and measurement techniques of their acoustic parameters were developed. Principal ultrasonic reconstruction of the real skull bone profile was accomplished.
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