Research carried out at UPV/EHU, DIPC and CNRS advances the understanding of electric contacts in future carbon-based nanoelectronics
Carbon-based nanostructures such as nanotubes, graphene sheets, and nanoribbons are unique building blocks showing versatile nanomechanical and nanoelectronic properties. These materials which are ordered in the nanoscale, that is, in the dimension of a millionth of millimetre, are promising candidates to envision applications in nanoscale devices, ranging from energy conversion to nano-electronic transistors.
A good connection between carbon-based materials and external metallic leads is of major importance in nanodevice performance, an aspect where an important step has been surmounted by researchers from UPV/EHU, DIPC and CNRS by studying contacts of carbon nanostructures with atoms of different chemical nature.
The chemical nature of contacting leads is of major importance as it affects the electronic properties and the geometry of the contact. The impact of these two aspects on the transport properties are entangled and this group studied these two parameters for contacts shrunk to the limit of individual atoms as for large structures it is challenging to address them separately.
In close collaboration, the researchers used a prototype carbon-based molecule made of 60 carbon atoms arranged in a sphere that can be viewed as a graphene sheet rolled into a tiny ball. The experimental team in Strasbourg led by Guillaume Schull, attached this molecule to the apex of an extremely tiny metal needle of a scanning tunnelling microscope.
The molecule-terminated needle was then cautiously approached to individual metallic atoms of different chemical nature up to the formation of a robust connection. By simultaneously measuring the electrical current passing through these connections, they could deduce which of the individual metallic atom is injecting charges to the carbon-made molecule with the greatest efficiency.
Large-scale computer simulations performed by the theoretical team in San Sebastian led by Thomas Frederiksen, Ikerbasque Research Professor at the DIPC, revealed a fascinating and unexpected aspect of these extremely tiny connections: their electric and mechanical properties are in fact representative for much larger carbon-based materials.
These results, published in the prestigious journal Nature Communications, set the bases to find extremely efficient contacts in the near future. The study paves the way to probe a great number of different metallic species (as well as tiny alloys made of two or three different metallic atoms), allowing for a systematic classification of their abilities to inject electrons into emerging carbon-based electronic devices.
Full research publication (open access)
Chemical control of electrical contact to sp2 carbon atoms
T. Frederiksen, G. Foti, F. Scheurer, V. Speisser, & G. Schul. Nature Communications (2014).
Thomas Frederiksen | Eurek Alert!
A big nano boost for solar cells
18.01.2017 | Kyoto University and Osaka Gas effort doubles current efficiencies
Multiregional brain on a chip
16.01.2017 | Harvard John A. Paulson School of Engineering and Applied Sciences
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences