1 million qubit quantum computers: moving beyond the current “brute force” strategy

More horsepower may not be the answer for the fledgling industry.

IBM’s Q System One quantum computer

 

By: John Levy, Co-Chief Executive Officer at Seeqc

Google, IBM, Intel, Microsoft and a handful of other large companies are engaged in a modern-day arms race to build the biggest, most powerful quantum computers imaginable. And while Google’s 53-qubit machine achieved an important proof of concept milestone in the form of quantum supremacy, the industry still largely has not provided proof that it can produce practical, business-ready quantum computers in the short term. 

To be clear, the work companies are doing to build larger and more powerful machines should not be underappreciated nor has it been a small task— it has been reported that at 100 qubits, a single quantum computer would be more powerful than all the supercomputers on the planet combined. Unlike classical computers that operate on bits, quantum computers become exponentially more powerful with each qubit added, posing seemingly limitless potential in their computing capabilities. 

But with billions of dollars of private and public investment being pumped into research, development and startups over the last few years, the industry is expected to show some kind of return on investment at some point. Industries such as pharmaceuticals, chemical and material manufacturing, logistics and defense with previously insurmountable challenges have demonstrated a business need for problem-specific quantum computers, but don’t yet have an application-specific solution available to them. 

The challenge of scaling 

Despite hefty investments and technological breakthroughs, current quantum computing systems and architectures are still inherently unstable and difficult to scale on a commercial level. Today’s machines still struggle with cost, readout and control challenges, as well as the complexities of managing heat generated by the microwave pulses used to control qubits. Heat management is a big hurdle for scaling quantum machines as leading state-of-the-art qubits need to be kept at near absolute zero temperatures to function, so as solutions include hundreds, even thousands of qubits — and maybe even more — cost, control and heat management greatly impact scale.

Several academic researchers have modeled just how difficult it is to manage heat loads when scaling up to even a 100 qubit machine. Researchers at ETH Zürich examined the rapidly increasing demand for the number of microwave and DC cables that need to be integrated when scaling from a few-qubit machine to a large-scale one.  

Adding to the challenge of heat management, the sheer cost of developing machines with a large number of qubits remains prohibitively expensive. By most estimates, a single qubit costs around $10K and needs to be supported by a host of microwave controller electronics, coaxial cabling and other materials that require large controlled rooms in order to function. 

In hardware alone, a useful quantum computer costs tens of billions of dollars to build. At that price point, quantum computers are only available to the largest and most wealthy enterprises, barring the majority of people from access to the technology. For innovation, it’s not ideal to rely on a handful of companies and institutions to advance an entire industry. More universal access would allow for faster, more meaningful innovation to take place across industries. 

The need for a more focused approach 

While building bigger and more expensive machines captures the media’s attention and pushes the boundaries of what will one day be possible, the approach simply doesn’t scale effectively as the industry strives to go from theoretical to business-applicable solutions. 

Seeqc is working on problem-specific applications to tackle the early use cases of quantum computing. We’re developing solutions that are energy-efficient, practical and scalable to meet the needs of businesses and early quantum computing adopters in the present day.

Seeqc is dedicated to providing business-ready quantum computing solutions, and we’re excited to say we’ll be sharing more details on our approach very soon.