Thermally stimulated currents of Zn-Bi-O thin film arresters

Ceramic varistors based on zinc oxide have excellent properties as protection devices used in power industry. However, their breakdown voltage, dependent on number of grain boundaries, is too high for use in electronic applications. In this work, performance of micro-devices having varistor-type current-voltage characteristics with low breakdown voltage is reported. The thermally stimulated depolarisation current (TSDC) technique was used to study the dielectric relaxation of the Zn-Bi-0 thin-film arresters. The surface varistor layers were prepared by r.f. magnetron sputtering on nickel support. The TSDC measuring system and cryostat apparatus used in experiment have been described

Local observables for entanglement witnesses

We present an explicit construction of entanglement witnesses for depolarized states in arbitrary finite dimension. For infinite dimension we generalize the construction to twin-beams perturbed by Gaussian noises in the phase and in the amplitude of the field. We show that entanglement detection for all these families of states requires only three local measurements. The explicit form of the corresponding set of local observables (quorom) needed for entanglement witness is derived.Comment: minor corrections, title change

Effects of prolonged and acute muscle pain on the force control strategy during isometric contractions

Musculoskeletal pain is associated with multiple adaptions in movement control. This study aimed to determine whether changes in movement control acquired during acute pain are maintained over days of pain exposure. On day 0, the extensor carpi radialis brevis muscle of healthy participants was injected with nerve growth factor (NGF) to induce persistent movement-evoked pain (n\ua0=\ua013) or isotonic saline as a control (n\ua0=\ua013). On day 2, short-lasting pain was induced by injection of hypertonic saline into extensor carpi radialis brevis muscles of all participants. Three-dimensional force components were recorded during submaximal isometric wrist extensions on day 0, day 4, and before, during, and after saline-induced pain on day 2. Standard deviation (variation of task-related force) and total excursion of center of pressure (variation of force direction) were assessed. Maximal movement-evoked pain was 3.3\ua0±\ua0.4 (0–10 numeric scale) in the NGF-group on day 2 whereas maximum saline-induced pain was 6.8\ua0±\ua0.3\ua0cm (10-cm visual analog scale). The difference in centroid position of force direction relative to day 0 was greater in the NGF group than in the control group (P\ua

Squeezing and entanglement in continous variable systems

Based on total variance of a pair of Einstein-Podolsky-Rosen (EPR) type operators, the generalized EPR entangled states in continuous variable systems are defined. We show that such entangled states must correspond with two-mode squeezing states whether these states are Gaussian or not and whether they are pure or not. With help of the relation between the total variance and the entanglement, the degree of such entanglement is also defined. Through analyzing some specific cases, we see that this method is very convenient and easy in practical application. In addition, an entangled state with no squeezing is studied, which reveals that there certainly exist something unknown about entanglement in continuous variable systems.Comment: 5 page

Quantum spin pumping mediated by magnon

We theoretically propose quantum spin pumping mediated by magnons, under a time-dependent transverse magnetic field, at the interface between a ferromagnetic insulator and a non-magnetic metal. The generation of a spin current under a thermal equilibrium condition is discussed by calculating the spin transfer torque, which breaks the spin conservation law for conduction electrons and operates the coherent magnon state. Localized spins lose spin angular momentum by emitting magnons and conduction electrons flip from down to up by absorbing the momentum. The spin transfer torque has a resonance structure as a function of the angular frequency of the applied transverse field. This fact is useful to enhance the spin pumping effect induced by quantum fluctuations. We also discuss the distinction between our quantum spin pumping theory and the one proposed by Tserkovnyak et al.Comment: 27 pages, 2 figures. v2; the detail of the calculation has been added in Appendix. The distinction from the spin pumping theory proposed by Tserkovnyak et al. has been clarified in section 5. v3; typos correcte

A tomographic approach to quantum nonlocality

We propose a tomographic approach to study quantum nonlocality in continuous variable quantum systems. On one hand we derive a Bell-like inequality for measured tomograms. On the other hand, we introduce pseudospin operators whose statistics can be inferred from the data characterizing the reconstructed state, thus giving the possibility to use standard Bell's inequalities. Illuminating examples are also discussed.Comment: 12 pages, 6 figures, IOP style, to appear in the Special Issue of J Opt.B connected with Wigner Centennial conference (references added and updated

Varistor performance of nanocrystalline Zn-Bi-O thin films prepared by reactive RF magnetron sputtering at room temperature

The Zn–Bi–O films were deposited by reactive radio frequency magnetron sputtering in oxygen atmosphere from ZnBi alloy target (wt. ratio Zn:Bi=9:1) on glass substrate at room temperature. The XRD patterns show that the films deposited on tin-doped indium oxide/glass substrates were nanocrystalline. The microstructure of Bi-doped ZnO films was studied by scanning electron microscopy in combination with energy dispersive X-ray spectroscopy. All the obtained layers had varistor-type non-linear current–voltage (I–V) characteristics with low breakdown voltage varying from few tenths of a volt to few volts

Thermally stimulated currents of Zn-Bi-0 thin film arresters

Ceramic varistors based on zinc oxide have excellent properties as protection devices used in power industry. However, their breakdown voltage, dependent on number of grain boundaries, is too high for use in electronic applications. In this work, performance of micro-devices having varistor-type current-voltage characteristics with low breakdown voltage is reported. The thermally stimulated depolarisation current (TSDC) technique was used to study the dielectric relaxation of the Zn-Bi-0 thin-film arresters. The surface varistor layers were prepared by r.f. magnetron sputtering on nickel support. The TSDC measuring system and cryostat apparatus used in experiment have been described.Керамические варисторы на основе оксида цинка обладают отличными свойствами как устройства защиты в энергетической промышленности. Однако их напряжения пробоя, зависящие от количества межзеренных границ, слишком высоки для использования в электронике. В настоящей работе описаны рабочие характеристики миниатюрных устройств, имеющих вольтамперные характеристики типа варисторных и низкие напряжения пробоя. Для исследования диэлектрической релаксации тонкопленочных Zn-Bi-0 разрядников применен метод тока термостимулированной деполяризации (ТТСД). Поверхностные слои варисторов получены методом высокочастотного магнетронного напыления на никелевой подложке. Описаны система для измерения ТТСД и криостат, использованные в работе.Керамічні варистори на основі оксиду цинку мають відмінні властивості як пристрої захисту в енергетичній промисловості. Проте їх напруги пробою, які залежать від кількості міжзеренних границь, є надто високими для застосування в електроніці. В роботі описано робочі характеристики мініатюрних пристроїв, які мають вольтам-перні характеристики типу варисторних та низькі напруги пробою. Для дослідження діелектричної релаксації тонкоплівкових Zn-Bi-0 розрядників застосовано метод струму термостимульованої деполяризації (СТСД). Поверхневі шари варисторів одержані методом високочастотного магнетронного напилення на нікелевій підкладці. Описано систему для вимірювання ТТСД та кріостат, які використані в роботі

Thermally stimulated currents of Zn-Bi-O thin film arresters

Ceramic varistors based on zinc oxide have excellent properties as protection devices used in power industry. However, their breakdown voltage, dependent on number of grain boundaries, is too high for use in electronic applications. In this work, performance of micro-devices having varistor-type current-voltage characteristics with low breakdown voltage is reported. The thermally stimulated depolarisation current (TSDC) technique was used to study the dielectric relaxation of the Zn-Bi-0 thin-film arresters. The surface varistor layers were prepared by r.f. magnetron sputtering on nickel support. The TSDC measuring system and cryostat apparatus used in experiment have been described

Self-Regenerative Property of Nanocrystalline Ce_0.89M_0.11O_2−y (M = Pd, Rh) Mixed Oxides

Self-regenerative properties of nanocrystalline Ce0.89M0.11O2−y (M=noble metal, e.g., Pd and Rh) mixed oxides were investigated by applying the reduction–oxidation treatment. These oxides were synthesised as chemically and structurally homogeneous powders (4–5 nm) with a large surface area (≈100 m2 g-1) by using the water-in-oil microemulsion method. The analysis of the reduced oxides revealed the presence of the crystalline M particles (size: 2 nm for Pd and 1 nm for Rh) that demonstrate a preferred orientation on the substrate—(1 1 1)M||(1 1 1)CeO2. The size and arrangement of the metal crystallites were the same after each reduction cycle. After oxidation treatment, the M particles disappeared but no distinct particles of an oxide phase (e.g., PdO or Rh2O3) could be detected. However, a thin amorphous layer was visible on the surface of Ce0.89Pd0.11O2−y crystallites. Temperature-programmed reduction of hydrogen and temperature-programmed oxidation confirmed the complete reversibility of the redox properties of Ce0.89Rh0.11O2−y after the reduction–oxidation treatment but only partial reversibility for Ce0.89Pd0.11O2−y