Featured Research

from universities, journals, and other organizations

Scientists develop force sensor from carbon nanotubes

Date:
June 30, 2014
Source:
Moscow Institute of Physics and Technology
Summary:
Scientists have developed a microscopic force sensor based on carbon nanotubes. The scientists proposed using two nanotubes, one of which is a long cylinder with double walls one atom thick. These tubes are placed so that their open ends are opposite to each other. Voltage is then applied to them, and a current of about 10nA flows through the circuit. Carbon tube walls are good conductors, and along the gap between the ends of the nanotubes the current flows thanks to the tunnel effect, which is a quantum phenomenon where electrons pass through a barrier that is considered insurmountable in classical mechanics.

Scientists proposed using two nanotubes, one of which is a long cylinder with double walls one atom thick. These tubes are placed so that their open ends are opposite to each other. Voltage is then applied to them, and a current of about 10nAflows through the circuit.
Credit: Image courtesy of Moscow Institute of Physics and Technology

A group of researchers from Russia, Belarus and Spain, including MIPT professor Yury Lozovik, have developed a microscopic force sensor based on carbon nanotubes. The device is described in an article published in the journal Computational Materials Science and is also available as a preprint.

The scientists proposed using two nanotubes, one of which is a long cylinder with double walls one atom thick. These tubes are placed so that their open ends are opposite to each other. Voltage is then applied to them, and a current of about 10nAflows through the circuit.

Carbon tube walls are good conductors, and along the gap between the ends of the nanotubes the current flows thanks to the tunnel effect, which is a quantum phenomenon where electrons pass through a barrier that is considered insurmountable in classical mechanics.

This current is called tunneling current and is widely used in practice. There are, for example, tunnel diodes, wherein current flows through the potential barrier of the p-n junction.

Another example is a scanning tunneling microscope (STM), in which the surface of a sample is scanned with a very sharp needle under voltage. The needle slides along the surface, and the magnitude of the current flowing through it shows the distance to the sample with such accuracy that the STM can detect protrusions one atom high.

The authors of the article used the relationship between the tunneling current and the distance between the ends of the nanotubes to determine the relative position of the carbon nanotubes and thus to find the magnitude of the external force exerted on them.

The new sensor allows the position of coaxial cylinders in two-layer nanotubes to be controlled quite accurately. As a result, it is possible to determine the stretch of an n-scale object, to which electrodes are attached. Calculations made by the researchers showed the possibility of recording forces of a few tenths of a nN(10-10newtons). To make it clearer, a single bacterium weighs about 10-14newtons on average, and a mosquito weighs a few dozen mcN (10-5 N).However, the device developed by the physicists may find application beyond micro scales.

A double-layered coaxial nanotube is akin to a microscopic cylinder with a sliding piston. Such a system has already been considered by a number of other researchers as a potential part for various types of nanomachines. Nanotubes have been proposed for the role of micromanipulators, or connecting "studs" for complex mechanisms, and they may even be used for data storage; the position of the inner "piston" may encode one bit of information or more.

Furthermore, calculations have shown that it is possible to create a combined device, where inside a two-layer carbon nanotube there will be magnetic fullerenes. When placed in a magnetic field, a power will emerge, which could be measured by changes in the magnitude of tunneling current. This will convert the force sensor into a magnetic field sensor.


Story Source:

The above story is based on materials provided by Moscow Institute of Physics and Technology. Note: Materials may be edited for content and length.


Journal Reference:

  1. Andrey M. Popov, Irina V. Lebedeva, Andrey A. Knizhnik, Yurii E. Lozovik, Nikolai A. Poklonski, Andrei I. Siahlo, Sergey A. Vyrko, Sergey V. Ratkevich. Force and magnetic field sensor based on measurement of tunneling conductance between ends of coaxial carbon nanotubes. Computational Materials Science, 2014; 92: 84 DOI: 10.1016/j.commatsci.2014.05.020

Cite This Page:

Moscow Institute of Physics and Technology. "Scientists develop force sensor from carbon nanotubes." ScienceDaily. ScienceDaily, 30 June 2014. <www.sciencedaily.com/releases/2014/06/140630103138.htm>.
Moscow Institute of Physics and Technology. (2014, June 30). Scientists develop force sensor from carbon nanotubes. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2014/06/140630103138.htm
Moscow Institute of Physics and Technology. "Scientists develop force sensor from carbon nanotubes." ScienceDaily. www.sciencedaily.com/releases/2014/06/140630103138.htm (accessed September 16, 2014).

Share This



More Matter & Energy News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
MIT's Robot Cheetah Unleashed — Can Now Run, Jump Freely

MIT's Robot Cheetah Unleashed — Can Now Run, Jump Freely

Newsy (Sep. 16, 2014) MIT developed a robot modeled after a cheetah. It can run up to speeds of 10 mph, though researchers estimate it will eventually reach 30 mph. Video provided by Newsy
Powered by NewsLook.com
Manufacturer Prints 3-D Car In Record Time

Manufacturer Prints 3-D Car In Record Time

Newsy (Sep. 15, 2014) Automobile manufacturer Local Motors created a drivable electric car using a 3-D printer. Printing the body only took 44 hours. Video provided by Newsy
Powered by NewsLook.com
Refurbished New York Subway Tunnel Unveiled After Sandy Damage

Refurbished New York Subway Tunnel Unveiled After Sandy Damage

Reuters - US Online Video (Sep. 15, 2014) New York officials unveil subway tunnels that were refurbished after Superstorm Sandy. Nathan Frandino reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins