Absorption properties of one- and two-dimensional semiconductor nanocrystals in the presence of an electric field

We have considered the broadening of optical absorption spectra of ensembles of randomly oriented nanorods and nanoplatelets that is caused by the action of a static electric field. It has been found that the linewidth in the spectra of the considered nanocrystals depends nonlinearly on the field strength and attains saturation in fields on the order of 100 kV/cm. We show that, due to a weak confinement, the electrooptical response of nanoplatelets is stronger than that of nanorods, which leads to a number of distinctive features in the field-induced broadening of the spectra of nanoplatelets and gives grounds to state that nanoplatelets are the most promising objects for use in electrooptical devices.     

The self-consistent response of the electron density of a crystal copper film to an external electrostatic field

The response of the electrons of an fcc copper (001) film to an external electrostatic field is calculated. In order to determine the distribution of the screening charge, the equations of the electron density-functional theory are solved self-consistently by an original method. The position of the “image plane,” which is involved in a correct asymptotic expression for the exchange-correlation potential in the vacuum region, is first determined when performing a quantum-mechanical calculation for an anisotropic crystal film. The nonlinear electron response is characterized by the evolution of the “center of gravity” of the induced charge, which is also investigated. The calculations take into account the crystal structure of the film, and the results differ essentially from the predictions of the “jelly” model.     

Modification planning in technical systems

Translated from Vychislitel'nye Kompleksy i Modelirovanie Slozhnykh Sistem, pp. 55–70, Moscow State University, 1989.     

Complexes of moving transversely one-dimensional laser solitons

Complexes of weakly coupled moving solitons are found by numerical solution of the generalized Ginzburg-Landau equation for the transversely one-dimensional scheme of a wide-aperture A-class laser with saturable absorption. As distinct from the case of complexes of motionless solitons, the phase difference between the neighboring moving solitons is close to 7π/2.     

Analysis of the Effect of Physico-Mechanical Characteristics of Cumulative Liner Material on Parameters of a High-Speed Element

Technical Physics - In this paper, we present the results of numerical simulation of explosive formation of a high-speed compact element from copper, steel, and aluminum cumulative liners combining...     

Extreme and Topological Nonlinear Optics of Open Systems

Optics and Spectroscopy - A review of results of an investigation of the theory of optical wave packets with extreme properties with respect to a controllable pulse shape or to the complexity of...     

Hydrogen Peroxide Decomposition Catalysts Used in Rocket Engines

Russian Journal of Applied Chemistry - The results of the development and studies of heterogeneous catalysts for decomposition of highly concentrated hydrogen peroxide used as monopropellant and...     

An Experimental Study of the Influence of a Magnetic Field of an Elongated Solenoid on Metal Shaped-Charge Jets Stretching

Technical Physics - The results of an experimental study of the influence of a longitudinal magnetic field of an elongated solenoid on stretching of metal shaped-charge jets in free flight are...