Ab initio study of mirages and magnetic interactions in quantum corrals

The state of the art ab initio calculations of quantum mirages,the spin-polarization of surface-state electrons and the exchange interaction between magnetic adatoms in Cu and Co corrals on Cu(111) are presented. We find that the spin-polarization of the surface-state electrons caused by magnetic adatoms can be projected to a remote location and can be strongly enhanced in corrals compared to an open surface.Our studies give a clear evidence that quantum corrals could permit to tailor the exchange interaction between magnetic adatoms at large separations. The spin-polarization of surface-state electrons at the empty focus in the Co corral used in the experimental setup of Manoharan et al., (Nature 403, 512 (2000)) is revealed.Comment: Submitted to Physical Review Letter

The parameters of cardiac rhythm in individuals of different age under the influence of physical activity

The research of the regularities of the adaptation's process of the organism associated with environment change is one of the most important problems of modern physiology and medicine. The given theme is actual nowadays, as it promotes the development of sports, helps to reach or improve sports achievements. The obtained results are used for the prevention and treatment of many diseases; allow us to identify opportunities for physiological mechanisms

Fully relativistic calculation of magnetic properties of Fe, Co and Ni adclusters on Ag(100)

We present first principles calculations of the magnetic moments and magnetic anisotropy energies of small Fe, Co and Ni clusters on top of a Ag(100) surface as well as the exchange-coupling energy between two single adatoms of Fe or Co on Ag(100). The calculations are performed fully relativistically using the embedding technique within the Korringa-Kohn-Rostoker method. The magnetic anisotropy and the exchange-coupling energies are calculated by means of the force theorem. In the case of adatoms and dimers of iron and cobalt we obtain enhanced spin moments and, especially, unusually large orbital moments, while for nickel our calculations predict a complete absence of magnetism. For larger clusters, the magnitudes of the local moments of the atoms in the center of the cluster are very close to those calculated for the corresponding monolayers. Similar to the orbital moments, the contributions of the individual atoms to the magnetic anisotropy energy strongly depend on the position, hence, on the local environment of a particular atom within a given cluster. We find strong ferromagnetic coupling between two neighboring Fe or Co atoms and a rapid, oscillatory decay of the exchange-coupling energy with increasing distance between these two adatoms.Comment: 8 pages, ReVTeX + 4 figures (Encapsulated Postscript), submitted to PR

Size-dependent Surface States on Strained Cobalt Nanoislands on Cu(111)

Low-temperature scanning tunneling spectroscopy over Co nanoislands on Cu(111) showed that the surface states of the islands vary with their size. Occupied states exhibit a sizeable downward energy shift as the island size decreases. The position of the occupied states also significantly changes across the islands. Atomic-scale simulations and ab inito calculations demonstrate that the driving force for the observed shift is related to size-dependent mesoscopic relaxations in the nanoislands.Comment: 4 pages, 4 figure

Application of passive filters for improvement of electromagnetic compatibility of network and induction motor soft starters

В статье рассмотрена эффективность применения фильтрокомпенсирующего устройства с тиристорным преобразователем напряжения, используемым для организации плавного пуска асинхронного двигателя. Изложена методика расчета параметров фильтров, приводятся результаты моделирования, показывающие значительное снижение уровня высших гармоник при использовании фильтрокомпенсирующего устройства, сделан вывод о целесообразности установки ФКУ в тиристорных системах плавного пуска АД.The paper discusses using of passive filters with thyristor soft starter. Filter parameters calculation procedure is described. Simulation results show that using of passive filters greatly reduce higher harmonics levels

International cooperation in combating illicit trafficking in cultural property

The paper discusses the basics of international cooperation in the field of combating illicit trafficking in cultural property. The directions of international cooperation in the field of combating illicit trafficking in cultural property and works of art are considered: interaction between international organizations, representatives of governments of UN member states, non-governmental organizations and the private secto