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In-space plasma propulsion is today a necessity for the economic competitiveness of commercial satellites. In plasma thrusters the impulse is imparted by a mesothermal plasma jet where ions drift a supersonic velocities. Compact multi-electrode systems for ion acceleration are studied by a combination of analytical calculations and computer simulations. The results show exahust speeds of 140 km/s can be reached with specific impulses higher than unsual plasma thrusters. Additionally, the ion velocity distribution functions of the plasma jet exhasut obtained with retarded field energy analyzers that can be used to cross validate the results of numerical simulations.

The advances made in telecommunication technologies imply that new functional materials are developed for the components used in advanced electronics. Creating biomolecular films with certain impedance characteristics for telecommunication devices is an urgent task. This paper presents the results of experiments on preparing thin films by dehydration of water-salt solutions of albumin protein on a dielectric substrate. Periodic cellular structures forming in the films during the phase transition were studied. The values of the parameters and the results of the experiments were refined by computer simulation. We reached a conclusion about the significant value of the electric micro-potential, electrical conductivity and the flow of local currents in such processes. Depending on the conditions of formation, various spatial, frequency and energy characteristics of the transmission of electrical signals through self-assembled biomolecular films can be achieved, making it possible to use these films to create devices and elements of advanced electronics and telecommunications.

The ionized states of molecular analytes located on solid surfaces require profound investigation and better understanding for applications in the basic sciences in general, and in the design of nanobiosensors, in particular. Such ionized states are induced by the interactions of molecules between them in the analyzed substance and with the target surface. Here, computer simulations using COMSOL Multiphysics software show the effect of surface charge density and distribution on the output generation in a dynamic PIN diode with gate control. This device, having built-in potential barriers, has a unique internal integration of output signal generation. The identified interactions showed the possibility of a new design for implementing a nanobiosensor based on a dynamic PIN diode in a mode with surface charge control.

In this paper, we study the processes related to a semiconductor sensor detection of electromagnetic wave irradiation. The distribution of the electric potential and the motion of the charge carriers in the semiconductor sensor with embedded gate-control potential barriers are under investigation using the computer simulation software Comsol Multiphysics. For the first time, the dependence on the accumulated dynamic charge concentration of the potential barriers height as a value used in analytical models was obtained. The appropriate mechanism of potential barriers and charge carrier dynamics and some possible applications were revealed and estimated.

Photodiodes detect the separation of charge carriers in a semiconductor upon irradiation with photons. Recently, new high sensitivity low noise photodetector-integrator based on a PIN diode with embedded gate-control potential barrier was developed. In the study of its characteristics, were observed effects of external particles on the surface of the substrate. In this paper, we studied the effect of surface charges on the potential distribution and charge carriers motion in such PIN diode by means computer simulation using the software Comsol Multiphysics. The appropriate mechanism of surface charge operation was revealed and estimated. The obtained results broaden the possibilities of using this PIN diode as a radiation detector, a particle detector, a biochemical sensor, etc.

Molecular communication systems became a promising paradigm of modern nanonetworks. Quantum carrier transfer creates communication channels between parts of a molecule and/or connects a few domains inside a molecular metamaterial network. This manuscript presents our studies of such channels activated by means of modulated laser beam irradiation resulting in molecular fluorescence, probably at a shifted frequency. The acquisition system for the electromagnetic field generated by a molecule based on the novel dynamic pin-photo diode is characterized by a high sensitivity and a low noise level due to the signal amplitude-time function integration.

Nano-devices with embedded molecular films appear as promising nano communications tools. In general, processing in such hybrid nano-device consists of initial energy of both activated electronic and atomic subsystems of an embedded molecular species, followed by intra- and inter-molecular nanoscale signals generation and reception of the transmitted signal at remote site. Actually, electromagnetic radiation can establish wireless nano communication in Visible, Infrared, and Microwave frequency ranges. In this manuscript, we estimate some properties of a microelectronics receiver in such systems, presented by novel dynamic operation pin photodetector, possesses signal integration, and required for receiving and demodulation of an electromagnetic wave. Revealed both theoretical and experimental characteristics of a photodetector have allowed designing dynamic process scenarios, as well as its possible applications inside a nano network.

The current paradigm in ion trap (cell) design for Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) is the ion detection with wide aperture detection electrodes. Specifically, excitation and detection electrodes are typically 90A degrees wide and positioned radially at a similar distance from the ICR cell axis. Here, we demonstrate that ion detection with narrow aperture detection electrodes (NADEL) positioned radially inward of the cell's axis is feasible and advantageous for FT-ICR MS. We describe design details and performance characteristics of a 10 T FT-ICR MS equipped with a NADEL ICR cell having a pair of narrow aperture (flat) detection electrodes and a pair of standard 90A degrees excitation electrodes. Despite a smaller surface area of the detection electrodes, the sensitivity of the NADEL ICR cell is not reduced attributable to improved excite field distribution, reduced capacitance of the detection electrodes, and their closer positioning to the orbits of excited ions. The performance characteristics of the NADEL ICR cell are comparable with the state-of-the-art FT-ICR MS implementations for small molecule, peptide, protein, and petroleomics analyses. In addition, the NADEL ICR cell's design improves the flexibility of ICR cells and facilitates implementation of advanced capabilities (e.g., quadrupolar ion detection for improved mainstream applications). It also creates an intriguing opportunity for addressing the major bottleneck in FTMS-increasing its throughput via simultaneous acquisition of multiple transients or via generation of periodic non-sinusoidal transient signals.

Non-Fourier transformation algorithm and computer program for efficient analysis of short broadband signals for the mass-spectrometry data transmission via wireless networks to remote data users have been developed and tested. It has been shown that even in the case no preliminary data on the signal phase parameters are available, short broad-band multicomponent transients can be transformed into high-resolution signals with high signal-to-noise ratios. Such signals are suitable for high-speed transmission via wireless networks.