Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Significant breakthrough in the design and production of electromechanical nanocomponents based on carbon nanotube structures

29.11.2005


Two studies on carbon nanotubes by CEA DRECAM researchers have just been published in Physical Review Letters and Applied Physics Letters. The first study presents an innovative and experimentally verified theoretical law to predict and characterize the deformation of a carbon nanotube subject to an electrical field. The second study applies this knowledge to produce a nano-switch using innovative dimensioning and positioning control techniques.



MEMs technologies (microelectromechanical systems) combine mechanical, optical, electromagnetic, thermal and fluidic concepts with electronics to produce chip-based integrated systems performing sensor and/or actuator functions. MEMs are currently used in a large number of sectors such as the automobile industry (airbag sensors), the computer peripherals industry (inkjet printer cartridges), and also the defense, medical and space industries. These technologies accompany the advances in microelectronic miniaturization. For sizes less than one micron, the term NEMs is used (nanoelectromechanical systems). However, below a certain size, entirely different production techniques must be employed, one the one hand due to preeminent surface effects very difficult to control, and the other because the physics of the phenomena is susceptible to change in the quantic realm.

Carbon nanotubes are excellent candidates for the production of NEMs. The assembly of nano-objects is an elegant solution to the increasing difficulty of machining massive materials at nanometric scale. A few examples of carbon nanotube NEMs have been published in the literature over the past 4 or 5 years. However, the development of this field of research was limited by the absence of dimensioning control tools for carbon nanotube NEMs.


The study by CEA DRECAM researchers published in Physical Review Letters is an important first step toward the development of generic dimensioning tools for carbon nanotube NEMs. It concerns a carbon nanotube attached at both ends and suspended above a conductor support. When voltage is applied to the conductor, the nanotube is subject to an attractive electrostatic force and deforms. The CEA researchers have derived a scale law that links the deformation of the nanotube to geometric parameters (diameter, suspended length, suspension height) and electrostatic parameters (applied voltage, voltage potential waveform). This law enables the dimensioning of all NEMs based on suspended and electrostatically activated nanotube structures. The researchers were able to verify this law using a technique to directly measure nanotube deformations by atomic force microscopy.

In Applied Physics Letters, the CEA researchers announce the production of a nano-switch by combining knowledge of carbon nanotube deformation under the effect of an electric field with a technique enabling controlled positioning of nanotubes on a surface. When a voltage potential is applied to a carbon nanotube, it deforms and comes into contact with an electrode. Although various teams throughout the world have already produced a few nanocomponents, the NEMs developed at the CEA involved the implementation of techniques to control the positioning of the nanotubes. This is an additional step toward the controlled production of nanocomponents with predefined properties. In addition, once the nanotube is in contact with the electrode, the Van Der Waals interactions maintain the contact even under very low voltage, which can be advantageously used for the production of memories.

Many applications can be considered for NEMs based on suspended and electrostatically deformed nanotubes, ranging from ultra-low force sensors to oscillators and high-frequency signal switches for telecommunications. The nano-switch and the electronic control system must be integrated on the same chip. This hybridization problem is at the heart of NANO-RF, a new European project coordinated by the Federal Polytechnic Institute of Lausanne and involving the participation of various CEA laboratories , the CNRS, and three other European partners.

Pascal Newton | alfa
Further information:
http://www.cea.fr

More articles from Physics and Astronomy:

nachricht Hope to discover sure signs of life on Mars? New research says look for the element vanadium
22.09.2017 | University of Kansas

nachricht Calculating quietness
22.09.2017 | Forschungszentrum MATHEON ECMath

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>