Quantum computing is here; Is a quantum PC next?

The Inside Quantum Technology Conference this week featured virtual panel of experts after virtual panel of experts laying out reasons why quantum computing is no longer a physicist’s pipe dream, and instead is real and here and brimming with potential to fuel a variety of projects and applications across many industries.

Although, “real and here” for most of us means in the cloud. That’s where many quantum computers, like IBM Quantum, exist today. Users, mostly researchers, students and other academic types, register to use cloud-based quantum computing resources. That’s why much of the market value of quantum computing in the next few years will be derived from cloud access to quantum computing resources and not from computing hardware and software components, as Lawrence Gasman, conference founder and president of IQT Research said during the event.

That begs two questions: Will cloud-based quantum computing ever give way to on-premises quantum computing, and if that’s possible, will we ever see such a thing as a quantum PC?

In a conference talk that he said attendees shouldn’t take “too seriously, with an emphasis on ‘too” Gasman speculated on those questions. There are three potential alternative methods for accessing quantum counting resources: the cloud model of today, the emerging notion of a quantum Internet and the possibility of a quantum desktops, that is to say rack mounted machines or table-sized units that could be used in data centers and similar environments.

The notion of a quantum internet was mentioned in passing by several conference panelists this week, and was the subject of a separate talk by Stephanie Wehner, roadmap leader of the quantum internet and network computing initiative at QuTech, who called the idea “something that sounds like a lofty goal, but is actually much more realistic.” She said the industry is making progress on quantum networks that consist of end nodes that currently can transmit qubits between them along a fiber route with repeaters in place for extended transmissions. This could enable applications such as advanced optical clock synchronization across networks and the creation of quantum computing clusters capable of more powerful computations and use cases than we see today

Gasman added during his discussion, “Quantum internet presupposes you have qubits on a network, and you’re moving qubits around” from one machine to another. He likened it to the early days of digital telecommunications, when “you had an analog line and could digitize things and run them through the analog lines.”

Quantum PCs

Such networks of quantum computers could see more on-premises quantum computing power centralized in physical locations as the industry develops quantum computers capable of storing and processing more qubits. Many of the largest computing, internet and cloud companies already are working on such machines, the latest example of which was announced this week in Google’s unveiling of plans for a “Quantum AI campus” in Santa Barbara, Calif. This includes a plan “to build 1,000,000 physical qubits that work in concert inside a room-sized error-corrected quantum computer,” stated Erik lucero, lead engineer, Google Quantum AI, in a blog post. “That’s a big leap from today’s modestly-sized systems of fewer than 100 qubits.”

Companies, let alone individuals, that don’t have the deep pockets and engineering battalions of a Google, IBM or Amazon Web Services, will be hard-pressed to develop or afford their own quantum computers anytime soon. However, the notion of a quantum PC also is becoming more realistic.

Gasman said the history of computing, in which room-sized mainframes evolved to mini-computers, which evolved to PCs, suggests what’s possible. The enabling of quantum technology in smaller form factors, via smaller, less costly, increasingly higher-performance quantum processors and other materials, could lead the way to quantum PCs.

In fact, Gasman highlighted the efforts of Chinese company SpinQ, which already boasts a $50,000 quantum computer that weighs in at 55 kilograms (about 121.5 lbs) and is available in China, Taiwan and Canada. “I wouldn’t like to carry 55 kilograms around,” Gasman said, but added later, “This is the nearest we’ve got to a quantum PC and shows that something like that could be built.”

SpinQ already has a much smaller, less pricey model in the works to be made available around the end of this year. It will cost less than $5,000 and be more portable, “and that means you could almost put it into John or Jennifer’s stocking” this holiday season, Gasman quipped. “It would have to be a big stocking.”

SpinQ’s current machines are around 2 qubits in processing power, and the company’s working on more powerful machines of three or four qubits, Gasman said. This is nowhere near the heavy-hitting plans of Google and the like, and quantum PCs in cost-efficient form factors that are capable of doing much more than current PCs are likely a very long way off.

“I don’t think clouds are going away anytime soon as the methodology of choice” for accessing quantum computing power and functionality, Gasman said.

However, noting the industry’s ability to quickly advance on technology roadmaps could have some surprises in store. “Until a year ago, it was still possible to deny the practicality of quantum computing,” he said. “Disruptive technology points the way to generally accessible technology. What seems impossible today may not seem impossible next time we have this conference.”

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