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The possibility of organizing multiuser access based on the differentially coherent information transmission scheme using chaotic radio pulses as data carriers has been demonstrated. Some theoretical estimates were made for the maximum number of subscribers and the information capacity of a multiuser system. Computer-aided modeling was performed to validate the obtained theoretical results.

The C–V characteristics of Au/Al2O3/In0.52Al0.48As and Au/SiO2/In0.52Al0.48As metal–insulator–semiconductor structures have been studied. It has been established that the fragmentary measurement of the C–V characteristics of InAlAs-based metal–insulator–semiconductor structures, in contrast standard registration method to at a constant voltage sweep rate, significantly weakens the effect of the hysteresis phenomena and allows one to record stationary curves. It is shown that the density of fast interface states calculated by the Terman method from such C–V characteristics slightly changes over the InAlAs band gap and amounts to (3–6) × 1011 and (1–3) × 1011 eV–1 cm–2 for MIS structures with Al2O3 and SiO2, respectively.

The presented experimental results demonstrate that microwave pulses of giant amplitude are generated in a klystron generator operating in the self-excited mode of chaotic oscillations. The auto-oscillator is assembled using a noisetron scheme that contains two five-cavity floating-drift klystrons serially connected in a ring, one of which operates in the mode of linear signal amplification (the linear klystron) and the other works in the mode of nonlinear signal amplification (the nonlinear klystron). It is established that, at a certain value of the beam current of a nonlinear klystron, intermittency of chaos–chaos type is realized in the auto-oscillation system in the form of chaotic sequences of microwave pulses of giant amplitude formed over the chaotic amplitude background. This type of intermittency is caused by the amplitude bistability of the nonlinear floating-drift klystron.

We consider the effect of the polarization characteristics of probe light on the signal of optically detected magnetic resonance in quantum sensors, including quantum magnetometers based on the phenomenon of electron paramagnetic resonance and quantum gyroscopes employing both the electron and nuclear magnetic resonance. Relationships between the magnetic resonance signal magnitude and parameters of the optical system elements, which are based on the Stokes–Mueller formalism, are derived and verified. It is found that the main destructive influence in the signal in a standard two-beam scheme is produced by phase delays introduced by both metallic and dielectric mirrors. Methods for compensation of this destructive influence are proposed and verified.

The possibility of wireless distance measurement using ultrawideband chaotic radio pulses on the basis of the statistical signal analysis is discussed. The results of experimental verification of the proposed approach are reported.

Growth-related structural defects present on the surface of InAlAs layers grown by molecular beam epitaxy on InP(001) substrates influence the temperature dependences of the current–voltage characteristics of Au/Ti/InAlAs Schottky barriers. It is established that these defects in the form of pits cause the appearance of regions with reduced barrier height. At a surface density of ≥107 cm–2, these defects significantly influence the parameters of the Schottky barriers at temperatures below 200 K.