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Transition metal-free half-metallicity recently has been the subject of intense research activity due to its potential in spintronics application. By employing density functional theory calculations, we revealed that F-intercalated GaN bilayers exhibit robust p orbital-based half-metallicity against the intercalant concentration and biaxial strain of −10% to 10%. The stable half-metallicity results from a spontaneous phase transition through Stoner instability and can be attributed to unusually high density of states near the Fermi level due to the quasi-flat bands. These findings provide a strategy to design transition-metal free half-metallic materials for futuristic spintronic applications. [ABSTRACT FROM AUTHOR]

A charge trapping memory device using Ti0.2Al0.8Ox film as charge trapping layer and amorphous Al2O3 as the tunneling and blocking layers was fabricated for nonvolatile memory application. TiAl2O5 nanocrystals are precipitated from the phase separation of Ti0.2Al0.8Ox film annealed at 900 °C. A memory window of 2.3 V and a stored electron density of 1×1013/cm2 were obtained. Good retention characteristics of the memory device at 80 °C were observed due to the deep charge trapping level as identified by the valence band offsets and electron energy loss spectrum measurements. [ABSTRACT FROM AUTHOR]

The microstructural evolution and resistive switching of glassy Ag30Ge17Se53 electrolyte films clipped by Ag active electrode, at which a positive bias was applied, and Pt inert electrode, were investigated by transmission electron microscopy observations and I-V measurements as functions of the period of electrical field treatment. It is revealed that an electrical field induced precipitation reaction forming conductive particles with orthorhombic Ag2Se structure and followed growth and networking of these particles, leading to an electrical percolation, are responsible for the transition from high resistive to high conductive state of the system. The kinetics of the precipitation reaction was also analyzed. [ABSTRACT FROM AUTHOR]

An organic bistable device with a structure Cu/Cu2S/copperphthalocyanine (Cu-Pc)/Pt was fabricated. Compared to the single layer organic device composed of Cu/Cu-Pc/Pt, the bilayer devices were observed to show distinct bistability with the resistance ratio of the off/on states up to 107 and low switch voltage (0.75–0.85 V). At least 105 switching cycles were achieved in the “write-read-erase-read” cycle voltage. The filament mechanism for the device is supported by the “metallic” behavior in their temperature dependence of the resistance in the on state. Such a memory device provides a promising structure for the nonvolatile memory. [ABSTRACT FROM AUTHOR]

The tunable property and thermal stability of (Ba0.25Pb0.25)Sr0.5TiO3 films derived by pulsed laser deposition have been investigated. The substitution of Pb for Ba in (Ba,Sr)TiO3 (BST) system has been revealed to raise the transition temperature close to room temperature (RT) and enhance the tuning property. It is proposed that nanopolar regions would occur in the films in the paraelectric state at RT, arising from the addition of Pb2+ into the A site of pervoskite structure of BST. This induces the relaxor behavior and diffuse phase transition. Hence, low temperature-dependent tunability is obtained due to the broadening of dielectric constant peak. These results demonstrated that Pb substitution could be a simple and effective method to obtain high tunability and good temperature stability simultaneously. [ABSTRACT FROM AUTHOR]

In this work, we present light-controlled resistive switches with p-Si/HfO2/Pt structures, in which the resistance can be controlled by a combination of electrical pulses and light. The devices have a large switching ratio (over 104) and good uniformity. Connecting two devices with a conventional resistor enables one to implement light-controlled material implication (IMP). Based on the light-controlled IMP logic, light-controlled NAND and light-controlled OR logic operations were also executed in the same devices. [ABSTRACT FROM AUTHOR]