IBM reports major advance in nanotube-based transistors

from the Molectronics dept.
According to a press release (20 May 2002), IBM announced it has created "the highest performing nanotubes transistors to date and has proven that carbon nanotubes can outperform the leading silicon transistor prototypes available today". According to the release, the IBM researchers were able to achieve the highest transconductance (measure of the current carrying capability) of any carbon nanotube transistor to date. The company said, "With the announcement, IBM is taking carbon nanotubes . . . another step closer to becoming an option for replacing silicon transistors in future devices."

The announcement garnered widespread attention. Read more for additional details of the research and selected press coverage, as well as links to posts on earlier IBM nanotube-related research.

Information Week highlights nanotechnology

The 13 May 2002 issue of the information technology industry trade journal Information Week contains an extensive feature article on nanotechnology ("The Next (Not So) Big Thing", by David M. Ewalt) that takes a quick, broad look at the field before narrowing down to its potential impact on the IT industry. In an accompanying editorial ("The Future Is Here And It's Verrry Small"), IW Editor Stephanie Stahl emphasizes the point that "nanotechnology has the potential to become one of those disruptive technologies that will dramatically change the way you do business".

The IW issue also contains several sidebars on current and potential applications of nanotech:

Thanks to Phil Wolff for submitting some of these items.

German researchers demonstrate light-driven nanoscale mechanism

Mr_Farlops writes "German researchers have developed a simple method to turn light into mechanical energy on the molecular scale. By shining light of one frenquency on an azobenzene molecule, they caused it to crimp and contract, pulling a load. By switching to another frequency, they caused the molecule to relax and stretch, releasing the tension."

Read more for details, links to web reports, and information on other research that indicates lasers can also be used to generate rotary motion in carbon nanotubes.

Coverage of Foresight Gathering focuses on Kurzweil-Stock debate

from the Loose-ends dept.
Hereís a small collection of coverage of the Foresight/IMM Senior Associates Gathering, held in Palo Alto, California, 26 to 28 April 2002:

carbon nanotubes as field emitters with MEMS

Brian Wang writes of news about "carbon nanotube as field emitters

The original paper is described in this abstract in Applied Physics Letters: ON-CHIP VACUUM MICROTRIODE. Integrated, solid-state design had many advantages over the old vacuum-tube style electronics. But some of the tube characteristics, such as the ability to handle high power, might be nice to have on a chip. With carbon nanotubes, acting as miniature emitters of electrons, this might be possible (See Update 454, http://www.aip.org/enews/physnews/1999/split/pnu45 4-2.htm). A new innovation in this regard is the development of an on-chip system of vacuum triodes. Scientists at Agere Systems (a company spun off from Lucent Technologies) build their chip using microelectromechanical (MEMS) technology; a lateral field of carbon nanotubes is grown on a cathode which can then be rotated into a vertical position in order to face a grid (10 microns away) and anode (100 microns away). Radar, electronic warfare, and satellite communications are expected to be the chief applications areas. (Bower et al., Applied Physics Letters, 20 May 2002)"

Forklifts for Nanoconstruction

Mr_Farlops writes "Scientists at Sandia National Laboratories have developed lipids that can grab and carry other molecules as they dart about on an artificial membrane that mimics those found in cells. Producing such a process is not novel however, the methods used to examine it and the insights gained from such examinations are. Because the movement of the lipids appears to be predictable and easy to control, the researchers speculate that such processes can be harnessed to aid in the construction of nanoscale devices."

Determining hardness of nanoscale materials

waynerad submitted this article from the Christian Science Monitor ("It's a small, small, small world", by Laurie Toupin, 14 May 2002) which he describes how an "MIT researcher uses atomic-force microscope (AFM) to determine the hardness of nanoscale materials. The NanoMechanical Technology Laboratory at MIT is using a diamond-tipped 'nano-indenter' to determine how materials behave at nanoscale dimensions. The nano-indenter measures the 'load' (force) being pushed into the sample and how deeply the diamond point goes into it, which gives enough information to calculate how stiff the material is, how strong it is, when it will fracture, and how much load it will take before it permanently deforms [breaks]."

U of L Chemical Engineers' Process Grows Crops of Nanowires

Judith Hughes at the University of Louisville (Kentucky, USA) submitted this press release on 13 May 2002: "U OF L CHEMICAL ENGINEERSí PROCESS GROWS CROPS OF NANOWIRES

LOUISVILLE, Ky. ñ University of Louisville chemical engineer Mahendra Sunkara, doctoral student Shashank Sharma and their research group have developed a process for growing nanometer-scale wires that allows them to control more easily the minute wiresí size, structure and composition."

More information is available at the UL Chemical Vapor Assisted Materials Synthesis Lab in the Chemical Engineering Department

Neural regeneration from stem cells

Stuart Scott writes "It appears that these researchers may be on to something very interesting. http://www.hhmi.org/news/stevens2.html"

Editor's note: What Stuart is referring to is the news in a press relase from the Howard Hughes Medical Institute (2 May 2002), which begins:

Researchers have discovered that astrocytes ó brain cells once thought to be little more than a component of the supportive scaffold for neurons ó may actually play a starring role in triggering the maturation and proliferation of adult neural stem cells. The studies also suggest that growth factors produced by astrocytes may be critical in regenerating brain or spinal tissue that has been damaged by trauma or disease.

Scientists Produce Long, Hair-Like Nanotubes

Two submissioins on this item:

waynerad writes "For the first time, researchers have created a simplified method for making long, continuous, hair-like strands of carbon nanotubes that are as much as eight inches in length. This breakthrough, reported in the May 3 issue of Science, is a first step toward creating such products as microcables for electrical devices or mechanically robust electrochemical actuators for artificial muscles.

The researchers from Rensselaer Polytechnic Institute and collaborators at Tsinghua University in Beijing found that chemical vapor deposition (CVD), a widely used technique to grow nanotubes, has a high yield of long strands when a sulfur-containing compound and hydrogen are added to the process."

And Brian Wang writes "For the first time, researchers have created a simplified method for making long, continuous, hair-like strands of carbon nanotubes that are as much as eight inches in length. This breakthrough, reported in the May 3 issue of Science, is a first step toward creating such products as microcables for electrical devices or mechanically robust electrochemical actuators for artificial muscles. The researchers from Rensselaer Polytechnic Institute and collaborators at Tsinghua University in Beijing found that chemical vapor deposition (CVD), a widely used technique to grow nanotubes, has a high yield of long strands when a sulfur-containing compound and hydrogen are added to the process. Researchers have previously created nanotube fibers with more complex methods, but because CVD is commonly used to make nanotubes, it would be easily adaptable and more efficient for synthesizing the long strands for practical applications. This new method produced nanotubes that measured 20 centimeters, much longer than conventional nanotubes, said Pulickel Ajayan. http://www.eurekalert.org/pub_releases/2002-05/rpi -spl050102.php"

0
    0
    Your Cart
    Your cart is emptyReturn to Shop