NEC

About: NEC is a company organization based out in Tokyo, Japan. It is known for research contribution in the topics: Signal & Layer (electronics). The organization has 33269 authors who have published 57670 publications receiving 835952 citations. The organization is also known as: NEC Corporation & NEC Electronics Corporation.

Control of Multiple Magnetic Domain Walls by Current in a Co/Ni Nano-Wire

Abstract: All-electrical control and local detection of multiple magnetic domain walls in perpendicularly magnetized Co/Ni nano-wires were demonstrated. A series of domain walls was reproducibly shifted in the same direction by the current, keeping the distance between the walls almost the same. Furthermore, the walls can be shifted back and forth depending on the direction of the pulsed currents.

Single-Wall Carbon Nanohorns and Nanocones

Abstract: In addition to sheet structures with purely hexagonal carbon rings, whichnaturally form surfaces of zero Gaussian curvature such as sheets and tubes, agraphenic membrane can also assume a conical shape whose apex is defined by one ormore disclinations taking the form of fivefold (or possibly smaller) rings.Geometrically, just as a sheet of paper with a wedge removed can be resealed to forma conical hat, a graphene sheet with a wedge removed (i.e., a disclination) can beresealed, notionally, to form a cone or horn. The single-wall carbon nanohorns(SWNH) form one class of such conical structures, with a particularly sharp apicalangle, a well-characterized high-yield synthesis route, and a distinct aggregatemicrostructure. Conical graphenic structures with wider opening angles,corresponding to fewer pentagonal disclinations at the apex, also form, sometimes asmultilayered structures. The pentagonal defects in carbon nanocones perturb thelow-energy electronic structure both locally and globally, defining both a localregion of enhanced reactivity and a global geometric phase relation withprofound consequences for electron transport around the apex. The rapidvariation in local sheet orientation around the cone and the two-dimensionalnature of the electronic states within imply that uniform laboratory fields cangenerate highly nonuniform effective local fields for states in the cone.

Method of generating duobinary signal and optical transmitter using the same method

Abstract: Disclosed is a method for generating a duobinary signal which has the step of: modulating individually an intensity and a phase of a carrier wave. Also disclosed is a duobinary-manner optical transmitter which has: a laser device which outputs signal light; an optical intensity modulator which intensity-modulates the signal light according to a first data signal generated by dividing a data signal into two signals; a precoder which inputs a second data signal generated by dividing the data signal into two signals; and an optical phase modulator which phase-modulates the intensity-modulated signal light according to a signal which is obtained delaying 0.5 bit an output signal of the precoder.

Low core losses and magnetic properties of Fe85-86Si1-2B8P4Cu1 nanocrystalline alloys with high B for power applications (invited)

Abstract: Recently, the energy crisis and the continued growth in electrical power generation strongly demand minimization of wasteful energy dissipation. Magnetic core loss (W) is the main source of energy dissipation in motors and transformers. This requires the development of soft magnetic materials with low coercivity (Hc) and high magnetic flux density (B). Fe-rich Fe85-86Si1-2B8P4Cu1 (at. %) alloy ribbons made from industrial raw materials (containing some impurities) with 6 mm in width have a heteroamorphous structure containing a large number of extremely small Fe grains (less than 3 nm), resulting from the unique effects of P and Cu addition in proper amounts. Crystallization of these alloys by annealing shows a uniform precipitation of α-Fe, leading to a uniform nanocrystallized structure of α-Fe grains, 16–19 nm in size, accompanied by an intergranular amorphous layer about 1 nm in width. The wide ribbons exhibit high B of 1.82–1.85 T (at 800 A/m), almost comparable to commercial oriented Fe–3 mass% Si a...