NEXAFS study of electronic and atomic structure of active layer in Al/indium tin oxide/TiO2 stack during resistive switching

We have studied the stability of the resistive switching process in the Al/(In₂O₃)_0.9(SnO₂)_0.1/TiO₂ assembly grown by atomic layer deposition. Besides electrical characterization the effect of electric field on the atomic electronic structure of the TiO₂ layer was studied using near edge X-ray absorption fine structure (NEXAFS) spectroscopy. The region of the current instability in the I-V characteristics was revealed. Presumably this current instability is supported by the amorphous structure of the TiO₂ film but is initiated by the surface morphology of the Al substrate. A formation of the O₂ molecules was established which occurs specifically in the region of the current instability that is a result of electrical Joule heating manifestation.     

DATA CLUSTERING USING A REORGANIZING NEURAL NETWORK

A new approach, designed for clustering of arbitrary distributed patterns, is presented. This study is concerned with the use of a self-organizing neural network as a frame for data clustering. The nearest network nodes in feature space are treated as prototypes, assigned to the corresponding cluster. The rules for dead-node shifting and simple adjustment of coordinates of the active nodes are introduced. The performance of the proposed self-organizing neural network is examined on the benchmark synthetic and the real-world problem.     

Piezoelectric effect in GaAs nanowires

The anomalous piezoelectric effect in GaAs nanowires was detected (the piezoelectric module d ₃₃ ≈ 26 pC/N). This result can be explained by the dominant content of the phase with the wurtzite-type crystal structure in GaAs nanowires and an increased pressing force on the contact layer.     

Numerical implementaion of a freezing-front model for water-saturated media that includes the dependence of the phase-transition temperature on the pressure and concentration

A computational algorithm is constructed for solution of the problem of freezing of water-saturated porous media with account for the dependence of the temperature of the phase transition of pore moisture on the pressure and the concentration of a dissolved impurity. The mathematical model of the process considered is based on a generalized formulation of the well-known Stefan problem. Examples convey results of computation.