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Scanning tunneling microscopy (STM) and spectroscopy (STS) investigations are made of highly oriented pyrolytic graphite (HOPG) in air and Langmuir‐Blodgett (LB) liquid crystalline films on HOPG. Charge density waves (CDW) on LB film surface and induced conductivity of LB film are discovered. Theoretical models for different tunneling mechanisms, explaining the experimental results are suggested. The influence of tip–sample interaction on forming additional resonant tunneling channels is analyzed. It is demonstrated, that the accurate information about electronic structure and symmetry of resonant states is necessary for correct STM data interpretation.

Structural properties of porous silicon were studied with atomic-force microscopy (AFM) and optical second harmonic generation (SHG). Depending on etching conditions, the SHG response was observed to be either anisotropic, showing C2v symmetry, or isotropic. This correlated with AFM observations of quasi ordered structures in the first case. The Si etching process was studied by in situ SHG measurements.

Force and surface devices with tunneling sensor—scanning tunneling and atomic force microscopes—are constructed. Thermal drift, seismic and electronic noise are eliminated in precise experiments. The tunneling sensor is proved to be advantageous for large scale images and force versus distance measurements with high dynamic range and subnanometer resolution. The influence of adsorbate on scanning tunneling microscope (STM) images of graphite is demonstrated. The holes 2 nm in diameter are produced on graphite exposed at air using STM.

We address the problem of noise regression in the output of gravitationalwave (GW) interferometers, using data from the physical environmental monitors (PEM). The objective of the regression analysis is to predict environmental noise in the GW channel from the PEM measurements. One of the most promising regression methods is based on the construction of Wiener-Kolmogorov (WK) filters. Using this method, the seismic noise cancellation from the LIGO GW channel has already been performed. In the presented approach the WK method has been extended, incorporating banks of Wiener filters in the time-frequency domain, multi-channel analysis and regulation schemes, which greatly enhance the versatility of the regression analysis. Also we present the first results on regression of the bi-coherent noise in the LIGO data.

Problems related to computer molecular modelling for imitation of tribosystem consisting of a couple of friction surfaces and a dividing lubrication layer have been studied. Tribological tasks that potentially can be resolved with the help of this concept and classification of the models used have been described. Principles of calculation environment organization for tribosystem models have been articulated. The main limitations of software and algorithmic solutions in this area have been listed. The potential of computer models for forecasting tribosystem parameters and new lubrication materials development have been evaluated and described.

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