Quantum computing just took a big leap based on building tiny quantum processors after the atomic model of natural molecules. Today, classical computers struggle to simulate even small molecules. There are just too many interactions between atoms. But now, researchers led by Professor Michelle Simmons have created an atomic-scale circuit that could transform everything.

Australian Simmons says it’s the “world’s first integrated circuit at the atomic scale.” 

It’s called an “analog quantum processor,” and this world’s first models the quantum states of a polyacetylene molecule. The discovery of the organic polymer with repeating chains led to the Nobel Prize in Chemistry in 2000. Due to its structure, the molecule has high electrical conductivity like metal.

As for the quantum circuit, it comprises 10 carbon-based quantum dots, tiny silicon semiconductors a few nanometers in size. Surrounding these precisely arranged dots are six metallic gates that control the flow of electrons through the circuit.

Simmons on 9 News Australia:

Computers that Mimick Nature

According to New Atlas, this research opens up study into how all kinds of molecules operate. 

“It sounds simple enough, but the key lies in the arrangement of these carbon atoms down to the sub-nanometer scale. Relative to each other, they’re precisely positioned to mimic the atomic structure of a particular molecule, allowing scientists to simulate and study the structure and energy states of that molecule more accurately than ever before,” writes Michael Irving.

According to the lead researcher Simmons, it’s like engineering atoms.

“Most of the other quantum computing architectures out there haven’t got the ability to engineer atoms with sub-nanometer precision or allow the atoms to sit that close,” said Simmons. “And so that means that now we can start to understand more and more complicated molecules based on putting the atoms in place as if they’re mimicking the real physical system.”

Nature at the Smallest Scale

In 2018, Simmons was named Australian of the Year for her work in quantum computing. 

“Trying to control nature at its very smallest scale is phenomenally exciting and rewarding, and has been my passion for many years,” Simmons said upon receiving the award. As a woman, she encourages “more girls to look at science,” and encourages more people to take on the challenge (see video below).

At the time, her group was the only one in the world “able to manipulate individual atoms to make atomically precise electronic devices,” stated UNSW Newsroom. Amazingly, they created the world’s first single-atom transistor and “the narrowest conducting wires ever made in silicon, just four atoms wide and one atom high.”

“Her achievements and those of her team are hugely exciting for UNSW and for Australia and she is an inspiration to all young people – and women in particular – who aspire to make a difference in the world,” said UNSW Dean of Science Professor Emma Johnston.

“Although Michelle’s work is conducted at the very smallest scale, its consequences will be enormous.”

Today, we see that Johnston was definitely correct about Simmons’ work.

Understanding Nature at the Atomic Level

Quite probably, the breakthrough opens up a new understanding of nature. In this case, the researchers studied how electricity moved through their circuit, which matched how currents move through polyacetylene molecules.

But in the near term, it also opens up the possibility that quantum computers could soon become commercially available. Already, the 10-atom processor can compete with what classical computers can do. 

When the researchers tested the processor, it completed a “tough task that classical computers struggle to complete,” stated IFLScience. For the task, the processor successfully modeled the quantum states of organic polyacetylene.

Next, University of New South Wales scientists plan to go to 20 atoms. However, to do so will require unbelievable precision. Unless all the quantum dots are uniformly spaced, electrons won’t pass through the gates.

According to IFLScience, prospects for the tiny circuits could also include:

• pharmaceuticals
• materials for batteries
• catalysts

Potentially, quantum computers will transform most industries, including health, finance, and transportation. 

“A quantum computer would be able to solve problems in minutes that would otherwise take thousands of years,” Simmons says.

Simmons appears on Sky News Australia:

Richard Feynman

Speaking about the breakthrough, Simmons credited American Nobel Prize winner Richard Feynman.

“If you go back to the 1950s, Richard Feynman said you can’t understand how nature works unless you can build matter at the same length scale,” Prof. Simmons said.

“And so that’s what we’re doing, we’re literally building it from the bottom up, where we are mimicking the polyacetylene molecule by putting atoms in silicon with the exact distances that represent the single and double carbon-carbon bonds.”

Feynman was known for his brilliant, unconventional mind and sometimes for sexism. Some have noted that he was a flawed character in this regard.

Building a Simulation of Nature

In 1981, Feynman threw down the gauntlet to build the first quantum computer at a conference. 

“Nature isn’t classical, dammit, and if you want to make a simulation of nature, you’d better make it quantum mechanical, and by golly it’s a wonderful problem, because it doesn’t look so easy,” he said.

As it turns out, a woman-led team answered his call. In a lecture, Simmons has previously credited British naturalist Henry Baker. In the 18th century, Baker tried to understand the world through its smallest scale in nature.

“Even back then, he saw that the real truth in the world came from understanding nature,” she said.

Simmons in a video by the Royal Society:

In the 40s, Feynman was the youngest group leader in the theoretical division of the Manhattan Project. As you may know, it was the U.S. government research project (1942–45) that produced the first atomic bombs. However, he is known for many achievements and transformed the field of quantum electrodynamics. 

Below, you can see him discuss physics in a way that most can appreciate on Fun to Imagine, created by the BBC in the 80s.

Featured image: polyacetylene by  Benjah-bmm27 via Wikimedia Commons, Public domain with images by geralt, Pixabay Pixabay License