Architecture and Hardware

The State of Quantum Computing

Inside a quantum computer at IBM.
A number of companies are working to develop practical quantum computing devices and deploy them for real commercial applications.

In December 2020, a Chinese research team claimed to have successfully achieved "quantum advantage" by using quantum computing methods to perform computations that classical supercomputers can't.

Using photons, the team carried out a calculation called a boson-sampling problem. The calculation has so many variables that existing supercomputers "would take half the age of Earth" to calculate the problem, according to Nature. The Chinese team used quantum computing to achieve the calculation in a few minutes.

"[This] is certainly an impressive academic achievement, showing that quantum machinery can in some cases strain the abilities of conventional computers," said Chris Monroe, co-founder and chief scientist of IonQ, a quantum computer maker developing what it describes as a general-purpose trapped ion quantum computer and software to generate, optimize, and execute quantum circuits. "But it's important to consider that the problem they solved is a narrow application space with no known practical use, and it will be difficult to tune their experiment for any other type of problem."

Several leading companies are working to avoid that problem by developing practical quantum machines and deploying them for real commercial applications.

D-Wave Systems is one such company at the forefront of recent quantum computing developments. British Columbia, Canada-based D-Wave makes quantum machines specifically for businesses. Last year, the company announced the general availability of Advantage, its 5,000-qubit quantum system, accompanied by its quantum cloud service, Leap. The company's machines take a unique approach to quantum computing called "quantum annealing," which uses the physics of quantum phase transitions to perform computations. The company bet big on annealing early on, a bet that it says has paid off.

Murray Thom, D-Wave's vice president of software and cloud services, said, "We believed—and still believe—that annealing is the fastest path to our number-one objective: fueling customer value through practical quantum applications." The company says over 250 quantum-powered applications built with its system are now in production from Fortune 500 companies like Volkswagen, DENSO, and Accenture.

IonQ of College Park, MD, is another quantum manufacturer with a big commercial footprint. The company uses individual atoms at the heart of their quantum processing units, resulting in machines with atomically perfect qubits. Last year, the company unveiled its most powerful system, with 32 perfect atomic clock qubits. IonQ's systems use a unique architecture of random-access processing of qubits in a fully connected and modular architecture, which the company claims presents a clear path for unlimited scale.

"By 2025, our commercial systems are expected to employ sufficient levels of quantum error correction to achieve broad quantum advantage," says IonQ co-founder and chief technology officer Jungsang Kim.

Established tech giants also are developing quantum hardware and cloud services.

Google last year used its Sycamore quantum processor to perform the largest quantum computation of chemistry calculations to date. The company also partnered with German pharmaceutical company Boehringer Ingelheim to research and implement quantum computing for drug design. This work shows progress towards real commercial and scientific use cases for quantum computing, according to a Google representative.

Microsoft announced its Azure Quantum cloud quantum computing platform for developers in 2019. A year later, the company became one of five founding members of the Quantum Science Center, a quantum computing center created in partnership with the U.S. Department of Energy. Companies like Ford already are experimenting with Azure Quantum to solve real-world problems, like traffic congestion, significantly faster than possible using classical computers. Azure Quantum leverages, among others, hardware from IonQ to provide quantum computing power.

Amazon's popular cloud computing platform is also getting a quantum makeover, with Amazon Braket now offering managed quantum cloud services for researchers and developers through Amazon Web Services. The system gives users access to both IonQ's quantum systems and D-Wave's quantum annealing capabilities.

Last, but certainly not least, IBM has 28 quantum computers deployed in commercial applications, working with companies like Mitsubishi Chemical, ExxonMobil, and Daimler to do everything from battery R&D to running chemistry simulations to improving auto manufacturing. The company plans to scale its quantum computing capabilities to a quantum machine with 1,121 qubits (to be called IBM Quantum Condor) by the end of 2023. To get a sense of the extnt of that progress, IBM released its 65-qubit quantum processor IBM Quantum Hummingbird in 2020 and has a 127-qubit processor planned for this year.

Thanks to rapidly improving quantum computing power, viable commercial use-cases, and expanded access to quantum via cloud services, the field is poised to have a very big year if developments continue apace.

"Quantum computing technology is accelerating rapidly, with new advancements and new companies getting involved nearly daily," says IonQ CEO and President Peter Chapman. "When I joined IonQ in 2019, people said that quantum would never work. We don't hear much from those people anymore."

Logan Kugler is a freelance technology writer based in Tampa, FL, USA. He has written for over 60 major publications.

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