Nanoelectronics breakthrough could lead to more efficient quantum devices

Their findings, which examine electron behaviour within nanoelectronics, have been published in the journal Nature Communications.

The article was co-authored by current PhD student Andrew McRae (MSc 13) and Alexandre Champagne, associate professor of physics in the Faculty of Arts and Science, along with two Concordia alumni, James M. Porter (MSc 15, BSc 11) and Vahid Tayari (PhD 14).

Champagne is pleased with the reception the research has garnered. "We were thrilled when our paper was accepted by Nature Communications because of the respect the journal has in the field," he says.

Champagne, the study's principle investigator, is also chair of Concordia's Department of Physics and the Concordia University Research Chair in Nanoelectronics and Quantum Materials.

Nature Communications is an open access, multidisciplinary journal dedicated to publishing research in biology, physics, chemistry and earth sciences. "The journal is known to publish advances of significance within each area," says Champagne.

The quantum nature of electrons

McRae, the paper's lead author, explains the research. "Our study sheds light on problems engineers face when building molecular nanoelectronics, and how they might be able to overcome them by harnessing the quantum nature of electrons," he says.

"We have shown experimentally that we can control whether or not positively and negatively charged particles behave the same way in very short carbon nanotube transistors. In particular, we have shown that in some devices of about 500 atoms long, the positive charges are more confined and act more like particles, while the negative charges are less well confined and act more like waves."

These results suggest new engineering possibilities. "This means that we can take advantage of the quantum nature of electrons to store information," says McRae.

Maximizing the differences between the way that positive and negative charges behave could lead to a new generation of two-in-one quantum electronic devices, he explains. The discovery could have applications in quantum computing, radiation sensing and transistor electronics.

This, in turn, could eventually lead to smarter and more efficient consumer electronics.

Ultra-short quantum transistors

"The most exciting implications are for building quantum circuits with single devices that can either store or pass quantum information along with the flick of a switch," says McRae.

"Our study also shows that we can build devices with dual capabilities, which could be useful in building smaller electronics and packing things in more tightly. In addition, these ultra-short nanotube transistors could be used as tools to study the interplay between electronics, magnetism, mechanics and optics, at the quantum level."