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.

Domain Wall Motion Induced by Electric Current in a Perpendicularly Magnetized Co/Ni Nano-Wire

Abstract: The authors show experimental results on domain wall motion induced by electric current in a Co/Ni nano-wire with perpendicular magnetic anisotropy. The motion was detected electrically by using the anomalous Hall effect. Threshold current density for the domain wall motion was found to decrease with decreasing the wire width, where the minimum threshold current density of approximately 5×1011 A/m2 was observed for the wire width of 70 nm.

Non-volatile semiconductor memory device having a metal-insulator-semiconductor gate structure and method for fabricating the same

Abstract: There is provided a metal-insulator-semiconductor gate insulating structure involved in a non-volatile memory device. A first insulating layer formed on the semiconductor substrate has a first dielectric constant e 1 and a first thickness of t 1 . A second insulating layer formed on the first insulating layer layer has a second dielectric constant e 2 and a second thickness of t 2 . A gate electrode of a metal layer is formed on the second insulating layer. The first and second dielectric constants e 1 and e 2 and the first and second thicknesses t 1 and t 2 satisfy the conditions of 20≦e 2 /e 1 , and t 2 /t 1 ≦e 2 /e 1 .

Filling factors, structural and electronic properties of C60 molecules in single-walled carbon nanotubes

Abstract: We report recent measurements of the electronic and structural properties of bulk samples of ${\mathrm{C}}_{60}$ molecules encapsulated in single-wall carbon nanotubes (so-called peapods) using electron-energy-loss spectroscopy in transmission. We demonstrate that ${\mathrm{C}}_{60}$ peapods with a single-wall carbon nanotube (SWNT) diameter distribution of $1.37\ifmmode\pm\else\textpm\fi{}0.08 \mathrm{nm}$ have an average fullerene filling of 60%. Regarding the electronic and optical properties, the overall shape of the response of the SWNT and the peapods is very similar, but with distinct differences in the fine structure. The interband transitions of the SWNT are slightly downshifted in the peapods, which can be explained by either a small increase of the SWNT diameter or by a change of the intertube interaction. The electronic and optical properties of the encapsulated ${\mathrm{C}}_{60}$ peas closely resemble those of solid fcc ${\mathrm{C}}_{60}$ showing small changes in the relative intensities, peak positions, and peak width, which point to a weak van der Waals interaction between the tubes and the encapsulated fullerenes.

Array-type processor

Abstract: A multiplicity of processor elements, which both individually execute data processing in accordance with instruction codes that have been set as data and for which mutual connection relations are switch-controlled, are arranged in matrix form, and the instruction codes of this multiplicity of processor elements are successively switched by a state control unit. The state control units are composed of a plurality of units that intercommunicate to realize linked operation, and the multiplicity of processor elements is divided into a number of element areas that corresponds to the number of state control units. The plurality of state control units are arranged for each of the plurality of element areas and are connected to the processor elements, whereby the plurality of state control units can individually control a plurality of small-scale state transitions, or the plurality of state control units can cooperate to control a single large-scale state transition.

Optical head comprising a diffraction grating for directing two or more diffracted beams to optical detectors

Abstract: For use in combination with an optical source for generating a coherent beam along a main optical axis, an optical head device comprises a diffraction grating having a plurality of grating regions which are responsive to the coherent beam for directing a zeroth-order diffracted beam to a focussing lens and are responsive to an optical beaem reflected from an optical recording medium for directing sidewards diffracted beams to an optical detector assembly. An effective area of a diameter of about 5 mm is sufficient for the diffraction grating. Each sidewards diffracted beam may form an angle of 20° with the main optical axis. The optical detector assembly is used in detecting focussing and tracking errors for the recording medium and can be used in reproducing optical information from the recording medium. A six-partitioned optical detector assembly is preferred when the grating regions are four in number. Either a four-partitioned or a three-partitioned optical detector assembly is preferred when the grating regions are two in number. Depending on the grating regions, the optical detector assembly preferably has two optical detector elements which are placed on different levels relative to the diffraction grating.