World’s smallest nanowire could result in quantum computers

World’s smallest nanowire could result in quantum computers


Scientists at the Centre for Quantum Computation and Communication Technology at the University of New South Wales in Sydney, Australia, have announced the creation of a nanoscale wire that conducts electricity.

The team announced the finding on Thursday, saying they have created a wire just four atoms high, with the ability to conduct electricity similar to that seen in copper wires. The wires are 20 times smaller than the smallest wires now available and measure just four atoms wide by one phosphorus atom tall.

The finding could lead to advances in the field of quantum computing, where such devices would rely on nanoscale technology. The wires would allow for the creation of powerful computers that could sift through massive amounts of data faster than current digital computers which use binary code.

“Driven by the semiconductor industry, computer chip components continuously shrink in size allowing ever smaller and more powerful computers,” said researcher Michelle Simmons, who headed the study.

Scientists were able to create the atom-sized wires in silicon using a technique called scanning tunneling microscopy, whereby they place chains of phosphorus atoms within a silicon crystal. Using atomic-scale wires covered in a silicon crystal with a layer of hydrogen atoms, the team carved out several-nanometer-wide channels in the hydrogen using the tip of a scanning tunnelling microscope.

At the level of four atoms, scientists said they expected electricity to defy convention physics and instead adhere to the laws of quantum mechanics. Instead, researchers say the wire displayed the same electrical properties as ordinary electrical interconnects, leading to speculation that the wires may have the ability to improve the possibility of quantum computing.

Each wire was prepared by lithographically writing lines onto a silicon sample with microscopy techniques and then depositing phosphorus along that line. By packing the phosphorus atoms close together and encasing the nanowires in silicon, the researchers were able to scale down without sacrificing conductivity, at least at low temperatures.

As manufacturing technology improves and costs fall, the number of transistors that can be squeezed onto an integrated circuit roughly doubles every two years. This trend, which is known as Moore’s law, has become a staple within the tech industry. However, with transistors now becoming so small, scientists have predicted that it may not be long before their performance is compromised by unpredictable quantum effects.

While the latest experiment shows that quantum computers may be possibility, researchers noted that the age of quantum computers remains at least ten years from now.