Featured Research

from universities, journals, and other organizations

Graphene nanoribbons as electronic switches

Date:
April 8, 2014
Source:
Springer Science+Business Media
Summary:
A new theoretical study shows the conductivity conditions under which graphene nanoribbons can become switches in externally controlled electronic devices. One of graphene's most sought-after properties is its high conductivity. Physicists have now successfully calculated the conditions of the transport, or conductance mechanisms, in graphene nanoribbons.

A new theoretical study shows the conductivity conditions under which graphene nanoribbons can become switches in externally controlled electronic devices.

One of graphene's most sought-after properties is its high conductivity. Argentinian and Brazilian physicists have now successfully calculated the conditions of the transport, or conductance mechanisms, in graphene nanoribbons. The results, recently published in a paper in The European Physical Journal B, yield a clearer theoretical understanding of conductivity in graphene samples of finite size, which have applications in externally controlled electronic devices.

When the conductivity is high, the electrons, carriers of electrical current, are minimally hampered during transport through graphene. One aspect of conductivity is the electron transport gap, which is the minimal energy required for electric current to pass through the material. The electron transport gap is an important factor for applications in electronic devices, because when the transport gap is controllable, it can be used as a switch in transistors -- the main components of any electronic device.

To study the electron transport gap, scientists prefer to use graphene nanoribbons, which can have variable crystallographic structures at their edges. In this EPJ B paper, the authors found that the transport gap is larger when the ribbon is narrower in width and that it is independent of the crystallographic orientation of the ribbon's edges.

The team found that the transport gap is inversely proportional to the ribbon's width and is independent of the crystallographic orientation of the ribbon's edges. Also, the conductance varies with the applied external voltage. These findings confirm previous theoretical and experimental results.

In addition, the authors focused on direct current conductivity, which is expected to jump through well-defined sharp steps, and referred to as quantisation. However, the authors' theoretical models present a somewhat different picture: the steps are not equally spaced and are not clearly separate but more blurred. By comparison, the conductance quantisation in graphene nanoribbons was previously observed experimentally in several works.

Unfortunately, none of the experiments can yet resolve the form of the steps. Further, the precision of existing measurements cannot yet clearly discriminate between different predictions for quantisation. More precise theoretical models are now required for a better understanding of the experimental behaviour of nanoribbons.


Story Source:

The above story is based on materials provided by Springer Science+Business Media. Note: Materials may be edited for content and length.


Journal Reference:

  1. Carlota G. Beneventano, Ignat Fialkovsky, Eve Mariel Santangelo, Dmitri V. Vassilevich. Charge density and conductivity of disordered Berry-Mondragon graphene nanoribbons. The European Physical Journal B, 2014; 87 (3) DOI: 10.1140/epjb/e2014-40990-x

Cite This Page:

Springer Science+Business Media. "Graphene nanoribbons as electronic switches." ScienceDaily. ScienceDaily, 8 April 2014. <www.sciencedaily.com/releases/2014/04/140408074855.htm>.
Springer Science+Business Media. (2014, April 8). Graphene nanoribbons as electronic switches. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2014/04/140408074855.htm
Springer Science+Business Media. "Graphene nanoribbons as electronic switches." ScienceDaily. www.sciencedaily.com/releases/2014/04/140408074855.htm (accessed August 21, 2014).

Share This




More Matter & Energy News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Flower Power! Dandelions Make Car Tires?

Flower Power! Dandelions Make Car Tires?

Reuters - Business Video Online (Aug. 20, 2014) Forget rolling on rubber, could car drivers soon be traveling on tires made from dandelions? Teams of scientists are racing to breed a type of the yellow flower whose taproot has a milky fluid with tire-grade rubber particles in it. As Joanna Partridge reports, global tire makers are investing millions in research into a new tire source. Video provided by Reuters
Powered by NewsLook.com
Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Newsy (Aug. 19, 2014) Scientists have developed a new device that mimics the way octopuses blend in with their surroundings to hide from dangerous predators. Video provided by Newsy
Powered by NewsLook.com
Researcher Testing on-Field Concussion Scanners

Researcher Testing on-Field Concussion Scanners

AP (Aug. 19, 2014) Four Texas high school football programs are trying out an experimental system designed to diagnose concussions on the field. The technology is in response to growing concern over head trauma in America's most watched sport. (Aug. 19) Video provided by AP
Powered by NewsLook.com
Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

AFP (Aug. 19, 2014) A solar cell that resembles a flower is offering a new take on green energy in Japan, where one scientist is searching for renewables that look good. Duration: 01:29 Video provided by AFP
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