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.

Si Nano-Photodiode with a Surface Plasmon Antenna

Abstract: Nano-photodiodes with a subwavelength active area using the optical near-field enhanced by surface plasmon resonance are proposed. We fabricated a Si Schottky photodiode that consists of an active area of 300 nm in diameter and a surface plasmon antenna to generate the carrier within the active area efficiently. The fabricated photodiode shows an increase of the photocurrent by several tenfold compared to that without a surface plasmon antenna. This result suggests an enhanced photogeneration of carriers in a semiconductor via surface plasmon resonance. Such a Si nano-photodiode is a potential high-speed optical signal detector because the opto-electronic conversion process occurs within a subwavelength scale.

Design and Characterization of Miniaturized Patch Antennas Loaded With Complementary Split-Ring Resonators

Abstract: An investigation into the design of compact patch antennas loaded with complementary split-ring resonators (CSRRs) and reactive impedance surface (RIS) is presented in this study. The CSRR is incorporated on the patch as a shunt LC resonator providing a low resonance frequency and the RIS is realized using the two-dimensional metallic patches printed on a metal-grounded substrate. Both the meta-resonator (CSRR) and the meta-surface (RIS) are able to miniaturize the antenna size. By changing the configuration of the CSRRs, multi-band operation with varied polarization states can be obtained. An equivalent circuit has been developed for the CSRR-loaded patch antennas to illustrate their working principles. Six antennas with different features are designed and compared, including a circularly-polarized antenna, which validate their versatility for practical applications. These antennas are fabricated and tested. The measured results are in good agreement with the simulation.

Guarded horn clauses

Abstract: A set of Horn clauses, augmented with a ‘guard’ mechanism, is shown to be a simple and yet powerful parallel logic programming language.

Semiconductor storage device

Abstract: A semiconductor storage device is provided with a memory array including a plurality of memory cells. The plurality of memory cells includes: first and third memory cells arranged along one of an even-numbered row and an odd-numbered row, and a second memory cell arranged along the other. Each of the plurality of memory cells includes: a first transistor comprising first and second diffusion layers; a second transistor comprising third and fourth diffusion layers; and a magnetoresistance element having one of terminals thereof connected to an interconnection layer which provides an electrical connection between the second and third diffusion layers. The fourth diffusion layer of the first memory cell is also used as the first diffusion layer of the second memory cell. In addition, the fourth diffusion layer of the second memory cell is also used as the first diffusion layer of the third memory cell.

Giant magnetoresistance in Ti 2 Mn 2 O 7 with the pyrochlore structure

Abstract: MATERIALS exhibiting giant magnetoresistance (GMR) undergo a large change in electrical resistance in response to an applied magnetic field. This effect is of technological interest as it can be exploited for the sensitive detection of magnetic fields in magnetic memory devices. A range of compounds have now been found to exhibit intrinsic GMR—these are all perovskites based on manganese oxide1–4. Here we report the observation of GMR in Ti2Mn2O7, which has a pyrochlore structure and thus differs both structurally and electronically from perovskites. At 135 K the magnetoresistance ratio (the change in resistance) reaches–86% at 7 tesla, comparable to the GMR response of perovskite materials. In contrast to the hole-doped perovskites, the charge carriers in our material are electrons, as determined from measurements of the Hall coefficient. The discovery of GMR in a second class of material expands the options for optimizing magnetoresistive properties for specific technological applications.