Magnetoelastic Coupling and Possibility of Spintronic Electromagnetomechanical Effects

Nanoelectromangetomechanical systems (NEMMS) open up a new path for the development of high speed autonomous nanoresonators and signal generators that could be used as actuators, for information processing, as elements of quantum computers etc. Those NEMMS that include ferromagnetic layers could be controlled by the electric current due to effects related with spin transfer. In the present paper we discuss another situation when the current-controlled behaviour of nanorod that includes an antiferro- (instead of one of ferro-) magnetic layer. We argue that in this case ac spin-polarized current can also induce resonant coupled magneto-mechanical oscillations and produce an oscillating magnetization of antiferromagnetic (AFM) layer. These effects are caused by \emph{i}) spin-transfer torque exerted to AFM at the interface with nonmagnetic spacer and by \emph{ii}) the effective magnetic field produced by the spin-polarized free electrons due to $sd$-exchange.The described nanorod with an AFM layer can find an application in magnetometry and as a current-controlled high-frequency mechanical oscillator.Comment: 8 pages, 2 figures, submitted to Low Temp. Physic

Electron spin resonance study on Mo-SiO₂ and Mo-TiO₂ with adsorbed benzene

The study is devoted to ESR-investigation of the primary processes upon chemisorption of benzene molecules onto the molybdenum supported on dispersed SiO₂ and TiO₂ samples. It has been confirmed that benzene chemisorption onto the Mo⁶⁺ species results in one-electron transfer in the ground state and paramagnetic species formation, namely reduced molybdenum species (Mo⁵⁺ species) and radicals of benzene. Computer treatment of ESR experimental data revealed that there are several types of Mo⁵⁺ species and benzene radicals, the assignment of which is proposed

Photoproduction of Long-Lived Holes and Electronic Processes in Intrinsic Electric Fields Seen through Photoinduced Absorption and Dichroism in Ca_3Ga_{2-x}Mn_xGe_3O_{12} Garnets

Long-lived photoinduced absorption and dichroism in the Ca_3Ga_{2-x}Mn_xGe_3O_{12} garnets with x < 0.06 were examined versus temperature and pumping intensity. Unusual features of the kinetics of photoinduced phenomena are indicative of the underlying electronic processes. The comparison with the case of Ca_3Mn_2Ge_3O_{12}, explored earlier by the authors, permits one to finally establish the main common mechanisms of photoinduced absorption and dichroism caused by random electric fields of photoproduced charges (hole polarons). The rate of their diffusion and relaxation through recombination is strongly influenced by the same fields, whose large statistical straggling is responsible for a broad continuous set of relaxation components (observed in the relaxation time range from 1 to about 1000 min). For Ca_3Ga_{2-x}Mn_xGe_3O_{12}, the time and temperature dependences of photoinduced absorption and dichroism bear a strong imprint of structure imperfection increasing with x.Comment: 20 pages, 10 figure

Institutional formation to develop tourism and recreation clusters

The article analyzes the specific features of the notion “institutional environment” and its impact on the effective functioning of the tourist and recreational clusters in Russia. The main components of the institutional environment influencing the development of the tourist and recreational clusters are considered in the article. The application of the given method allows to propose the authors’ vision of the institutional environment as an economic policy. The authors single out the main economic relations being formed in the institutional environment and providing the effective development of the tourist and recreational clusters as the element of the economic system.peer-reviewe