<![CDATA['Atomic origami': Chinese scientists master the art of folding graphene]>
Chinese scientists have taken the ancient art of origami to the atomic level by finding a way to fold microscopically small graphene, according to a new study.
The team managed to fold a 20 nanometre wide sheet of graphene into various shapes and forms using an extremely sharp needle with a single electrically charged atom at the tip, according to a paper published in the latest edition of Science magazine.
The breakthrough could eventually enable a host of technological advances, including the development of faster and more powerful computer processors, the researchers said.
"This is the world's smallest origami work," said Dr Du Shixuan, the study's lead scientist, adding that the team hoped to build on their success by making the graphene equivalent of a paper aeroplane.
Unlike previous experiments, in which the folding occurred randomly or by accident, the new technology allows scientists to control the transformation with atomic-scale accuracy, according to Du, from the Institute of Physics at the Chinese Academy of Sciences in Beijing.
Microscopic images of the graphene folding process. Photo: Handout alt=Microscopic images of the graphene folding process. Photo: Handout
Zhang Gengmin, a professor of physics at Peking University, said the team had managed something that other scientists had spent years trying to achieve.
Zhang, who was not involved in the study, said part of the difficulty was that atomic particles were influenced by quantum mechanics, a branch of physics whose laws are counter-intuitive to our daily experience.
In practice this means that folding a graphene sheet in one direction might cause it go in another direction or simply break apart.
The new technology developed by Du's team could have some critical applications, according to Zhang, who works at the university's nano devices laboratory.
For instance, folding a sheet of graphene " formed from a single layer of latticed carbon atoms " into a "magic angle" will make it superconductive, a unique physical state that allows electrons to pass through without any resistance.
"It is a significant piece of work," he said.
The 20 nanometre wide sheet was folded into various shapes. Photo: Handout alt=The 20 nanometre wide sheet was folded into various shapes. Photo: Handout
The paper by Du's team withheld some of the technical details of their experiment, which means that other scientists may not be able to replicate the process simply by reading the paper.
Du defended the secrecy as a standard practice and necessary measure to maintain China's lead in this field.
She said that the team's success was down to many factors " including the hardware used, the strength of the electric current and the experience of the operator " and there were also lessons to be taken from their previous failed attempts.
The researchers said they hoped the technology would be used to improve the design and manufacturing of computer processors.
At present, commercial processors are made using a large piece of silicon board known as a wafer.
But as the size of components such as transistors shrink, it has become increasingly difficult to improve the speed and performance of the computer due to the challenges of controlling the structure and properties of each component on a near-atomic scale
The new technology could give designers more freedom to develop a "dream chip" by building a central processing unit on an atom-by-atom basis from the bottom up.
But Du said the commercial application of the new technology could be years away.
Her team folded the graphene sheets manually, one at a time, but mass production would need the development of new manufacturing methods to do it automatically. At present "we are working on it", Du added.
This article originally appeared on the South China Morning Post (SCMP).
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