Tag: ‘Nanotech’

Polygonal spiral-shaped carbon nanotubes discovered

10 May 2006

Carbon nanotubeOn May 8, researchers from JFE Holdings, Inc. and Shinshu University announced the discovery of a new type of carbon nanotube (CNT) -- a polygonal tube shaped in a spiral configuration. Cross-sections of what are normally round tubes showed a structure with at least six sides.

This special structure appeared in CNTs that were synthesized using JFE's production method. The researchers speculate that the polygonal tube spirals arise because the production method’s high temperatures (over 3000 degrees Celsius) lead to high crystallinity, and the rapid cooling causes distortion in the crystal structure.

Using an arc discharge method of production, the company has succeeded in synthesizing 100-micrometer (1 micrometer = 1 millionth of a meter) thick CNT tape comprised of tubes with a purity of nearly 100%. This tape, according to the researchers, is the world’s first of its kind.

When the researchers analyzed the new CNT structure, they found that electron emission was at least several times better than conventional cylindrical CNTs, and they discovered that its strength as a material was at least dozens of times greater.

The company has begun test marketing the polygonal nanotubes, which they call nanocores, for applications in electronics and composite materials. Carbon nanotube tape can be used for such products as field emission displays, next-generation flat-panel displays, fuel cells and semiconductor parts.

[Source: Fuji Sankei]

Stacks of ultra-thin DVDs approach terabyte level

20 Apr 2006

On April 19, Hitachi Maxell, Ltd. announced the development of new volume optical storage technology that can provide terabyte-level storage capacity in a compact device. Relying on unique nanoimprint technology, the company has succeeded in reducing the thickness of DVDs to 0.092 mm (92 micrometers) -- which is 1/13th the thickness of current DVDs -- while maintaining the standard capacity of 4.7 GB.

Hitachi Maxell's thin DVD

The system features what the company calls Stacked Volumetric Optical Disc (SVOD) technology, which consists of 100 ultra-thin optical discs (12-cm in diameter, the same as current DVDs) loaded into a 6.5-cm (2.5-inch) thick cartridge. The result is a compact optical disc library system (1/10th the conventional size) capable of combining random access memory and long-term storage.

When laminated on both sides, disc capacity will reach 9.4 GB, bringing the 100-disc cartridge up to near-terabyte level with 940 GB of storage. The company claims that next-generation blue laser technology could boost cartridge capacity to 5 terabytes (50 GB for each double-sided disc).

According to Hitachi Maxell, potential applications of this storage media include library systems for business and institutions. While continuing to investigate other applications, the company aims to cultivate the market by presenting this technology at academic conferences and exhibitions.

The discs will be priced at under 40,000 yen (US$325) for a stack of 100.

[Source: IT Media, Hitachi Maxell press release]

Through the (zero-reflection) looking glass

07 Apr 2006

MetamaterialWhen light passes through material such as glass, a portion of its energy is lost as it reflects off the material's surface. Researchers at Japan's Institute of Physical and Chemical Research (Riken) have come up with a theoretical design for preventing this phenomenon from occurring.

The researchers have designed a prism of engineered material -- metamaterial comprised of an arrangement of nano-coils of precious metals such as gold or silver -- embedded in a solid glass-like material. The prism structure has a negative refractive index, which makes it truly transparent to light, allowing it to pass freely through with no reflection.

In the future, this type of metamaterial prism could lead to improvements in low-loss fiber optic communications, the development of telescopes and cameras well-suited for dark subjects, and the emergence of optical equipment we have never seen before.

[Sources: Jiji, Riken press release]