Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > ‘Missing jigsaw piece’: engineers make critical advance in quantum computer design

Dr Jarryd Pla and Professor Andrew Dzurak have solved the problem of how to reliably control not just a few, but millions of qubits. Photo: UNSW
Dr Jarryd Pla and Professor Andrew Dzurak have solved the problem of how to reliably control not just a few, but millions of qubits. Photo: UNSW

Abstract:
Quantum engineers from UNSW Sydney have removed a major obstacle that has stood in the way of quantum computers becoming a reality: they discovered a new technique they say will be capable of controlling millions of spin qubits – the basic units of information in a silicon quantum processor.

‘Missing jigsaw piece’: engineers make critical advance in quantum computer design

Sydney, Australia | Posted on August 20th, 2021

Until now, quantum computer engineers and scientists have worked with a proof-of-concept model of quantum processors by demonstrating the control of only a handful of qubits.

But with their latest research, published today in Science Advances, the team have found what they consider ‘the missing jigsaw piece’ in the quantum computer architecture that should enable the control of the millions of qubits needed for extraordinarily complex calculations.

Dr Jarryd Pla, a faculty member in UNSW’s School of Electrical Engineering and Telecommunications says his research team wanted to crack the problem that had stumped quantum computer scientists for decades: how to control not just a few, but millions of qubits without taking up valuable space with more wiring, using more electricity, and generating more heat.

“Up until this point, controlling electron spin qubits relied on us delivering microwave magnetic fields by putting a current through a wire right beside the qubit,” Dr Pla says.

“This poses some real challenges if we want to scale up to the millions of qubits that a quantum computer will need to solve globally significant problems, such as the design of new vaccines.

“First off, the magnetic fields drop off really quickly with distance, so we can only control those qubits closest to the wire. That means we would need to add more and more wires as we brought in more and more qubits, which would take up a lot of real estate on the chip.”

And since the chip must operate at freezing cold temperatures, below -270°C, Dr Pla says introducing more wires would generate way too much heat in the chip, interfering with the reliability of the qubits.

“So we come back to only being able to control a few qubits with this wire technique,” Dr Pla says.

Lightbulb moment

The solution to this problem involved a complete reimagining of the silicon chip structure.

Rather than having thousands of control wires on the same thumbnail-sized silicon chip that also needs to contain millions of qubits, the team looked at the feasibility of generating a magnetic field from above the chip that could manipulate all of the qubits simultaneously.

This idea of controlling all qubits simultaneously was first posited by quantum computing scientists back in the 1990s, but so far, nobody had worked out a practical way to do this – until now.

“First we removed the wire next to the qubits and then came up with a novel way to deliver microwave-frequency magnetic control fields across the entire system. So in principle, we could deliver control fields to up to four million qubits,” says Dr Pla.

Dr Pla and the team introduced a new component directly above the silicon chip – a crystal prism called a dielectric resonator. When microwaves are directed into the resonator, it focuses the wavelength of the microwaves down to a much smaller size.

“The dielectric resonator shrinks the wavelength down below one millimetre, so we now have a very efficient conversion of microwave power into the magnetic field that controls the spins of all the qubits.

“There are two key innovations here. The first is that we don’t have to put in a lot of power to get a strong driving field for the qubits, which crucially means we don’t generate much heat. The second is that the field is very uniform across the chip, so that millions of qubits all experience the same level of control.”

Quantum team-up

Although Dr Pla and his team had developed the prototype resonator technology, they didn’t have the silicon qubits to test it on. So he spoke with his engineering colleague at UNSW, Scientia Professor Andrew Dzurak, whose team had over the past decade demonstrated the first and the most accurate quantum logic using the same silicon manufacturing technology used to make conventional computer chips.

“I was completely blown away when Jarryd came to me with his new idea,” Prof. Dzurak says, “and we immediately got down to work to see how we could integrate it with the qubit chips that my team has developed.

“We put two of our best PhD students on the project, Ensar Vahapoglu from my team, and James Slack-Smith from Jarryd’s.

“We were overjoyed when the experiment proved successful. This problem of how to control millions of qubits had been worrying me for a long time, since it was a major roadblock to building a full-scale quantum computer.”

Once only dreamt about in the 1980s, quantum computers using thousands of qubits to solve problems of commercial significance may now be less than a decade away. Beyond that, they are expected to bring new firepower to solving global challenges and developing new technologies because of their ability to model extraordinarily complex systems.

Climate change, drug and vaccine design, code decryption and artificial intelligence all stand to benefit from quantum computing technology.

Looking ahead

Next up, the team plans to use this new technology to simplify the design of near-term silicon quantum processors.

“Removing the on-chip control wire frees up space for additional qubits and all of the other electronics required to build a quantum processor. It makes the task of going to the next step of producing devices with some tens of qubits much simpler,” says Prof. Dzurak.

“While there are engineering challenges to resolve before processors with a million qubits can be made, we are excited by the fact that we now have a way to control them,” says Dr Pla.

####

For more information, please click here

Contacts:
Lachlan Gilbert

Office: 040-419-2367
Expert Contacts

Dr Jarryd Pla

Cell: +61 426-117-130
Professor Andrew Dzurak

Cell: +61 432-405-434
Dr Ensar Vahapoglu

Cell: +61 410776102

Copyright © UNSW Sydney

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

ARTICLE TITLE

Related News Press

News and information

Drawing data in nanometer scale September 30th, 2022

Researchers unveil mystery inside Li- o2 batteries September 30th, 2022

Synthesis of air-stable room-temperature van der Waals magnetic thin flakes September 30th, 2022

ACM Research Launches New Furnace Tool for Thermal Atomic Layer Deposition to Support Advanced Semiconductor Manufacturing Requirements: Ultra Fn A Furnace Tool Shipped to China-Based Foundry Customer September 30th, 2022

Possible Futures

Researchers unveil mystery inside Li- o2 batteries September 30th, 2022

Synthesis of air-stable room-temperature van der Waals magnetic thin flakes September 30th, 2022

Layer Hall effect and hidden Berry curvature in antiferromagnetic insulators September 30th, 2022

ACM Research Launches New Furnace Tool for Thermal Atomic Layer Deposition to Support Advanced Semiconductor Manufacturing Requirements: Ultra Fn A Furnace Tool Shipped to China-Based Foundry Customer September 30th, 2022

Chip Technology

Conformal optical black hole for cavity September 30th, 2022

Synthesis of air-stable room-temperature van der Waals magnetic thin flakes September 30th, 2022

ACM Research Launches New Furnace Tool for Thermal Atomic Layer Deposition to Support Advanced Semiconductor Manufacturing Requirements: Ultra Fn A Furnace Tool Shipped to China-Based Foundry Customer September 30th, 2022

Key element for a scalable quantum computer: Physicists from Forschungszentrum Jülich and RWTH Aachen University demonstrate electron transport on a quantum chip September 23rd, 2022

Quantum Computing

Synthesis of air-stable room-temperature van der Waals magnetic thin flakes September 30th, 2022

Chicago Quantum Exchange welcomes six new partners highlighting quantum technology solutions, from Chicago and beyond September 23rd, 2022

Upgrading your computer to quantum September 23rd, 2022

Key element for a scalable quantum computer: Physicists from Forschungszentrum Jülich and RWTH Aachen University demonstrate electron transport on a quantum chip September 23rd, 2022

Discoveries

Surface microstructures of lunar soil returned by Chang’e-5 mission reveal an intermediate stage in space weathering process September 30th, 2022

Researchers unveil mystery inside Li- o2 batteries September 30th, 2022

Synthesis of air-stable room-temperature van der Waals magnetic thin flakes September 30th, 2022

Layer Hall effect and hidden Berry curvature in antiferromagnetic insulators September 30th, 2022

Announcements

Researchers unveil mystery inside Li- o2 batteries September 30th, 2022

Synthesis of air-stable room-temperature van der Waals magnetic thin flakes September 30th, 2022

Layer Hall effect and hidden Berry curvature in antiferromagnetic insulators September 30th, 2022

ACM Research Launches New Furnace Tool for Thermal Atomic Layer Deposition to Support Advanced Semiconductor Manufacturing Requirements: Ultra Fn A Furnace Tool Shipped to China-Based Foundry Customer September 30th, 2022

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers/Posters

Conformal optical black hole for cavity September 30th, 2022

Cleveland researchers reveal new strategy to prevent blood clots without increasing the risk of bleeding: University Hospitals and Case Western Reserve University findings may be especially impactful for cancer patients who experience blood clot complications September 30th, 2022

Ultrasmall VN/Co heterostructure with optimized N active sites anchored in N-doped graphitic nanocarbons for boosting hydrogen evolution September 30th, 2022

Layer Hall effect and hidden Berry curvature in antiferromagnetic insulators September 30th, 2022

Quantum Dots/Rods

Research improves upon conventional LED displays: With new technology, LEDs can be more cost-efficient and last longer September 9th, 2022

Lattice distortion of perovskite quantum dots induces coherent quantum beating September 9th, 2022

Newly developed technique to improve quantum dots color conversion performance: Researchers created perovskite quantum dot microarrays to achieve better results in full-color light-emitting devices and expand potential applications June 10th, 2022

Development of a single-process platform for the manufacture of graphene quantum dots: Precisely controls the bonding configuration of heteroatoms in graphene quantum dots through simple chemical processes. Practical application and commercialization in various fields is expected December 3rd, 2021

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project