DARPA's quantum computing is powered by ... FOMO

Fujitsu may not be worried about encryption busting quantum computers showing up anytime soon, but that doesn’t mean the US government is willing to risk missing out.

This week the Defense Advanced Research Agency (DARPA), the US military's boffin brain farm, announced a new endeavor, called the Underexplored Systems for Utility-Scale Quantum Computing (US2QC) program, to explore novel quantum system designs, and tapped Microsoft, Atom, and PsiQuantum to help.

“Experts disagree on whether a utility-scale quantum computer based on conventional designs is still decades away or could be achieved much sooner,” Joe Altepeter, who leads DARPA’s US2QC program, said in a statement. “The goal of US2QC is to reduce the danger of strategic surprise from underexplored quantum computing systems.”

In other words, if it is possible to build a quantum computer capable of breaking through encryption or compromising the United States’ defenses in any capacity, DARPA doesn’t want to be caught playing catch up with rival nations.

The idea that quantum computers could render existing encryption methods ineffective has been floated for years and driven investments into quantum-safe encryption methods. Bug it has never been proven to work, that we know about at least.

Under the US2QC program, the DARPA will work with and provide funding to these companies as they develop a design concept for a “utility-scale” quantum computer. This refers to a quantum system that’s more than a science project and is capable of generating computational values greater than its cost.

According to Altepeter, the three companies were selected based on a number of criteria. “We put out a call last year saying that if anyone thought they had a truly revolutionary approach to building a useful quantum computer in the near future – less than 10 years – we wanted to hear from them,” he explained.

• Seattle: Home of grunge, Starbucks… and now, a quantum computer manufacturing plant
• Fujitsu: Quantum computers no threat to encryption just yet
• China's Baidu enters quantum computing chat with Qian Shi system
• Chinese researchers' claimed quantum encryption crack looks unlikely

Microsoft, Atom, and PsiQuantum were ultimately selected, and unsurprisingly, the agency has hedged its bets as to the technologies that will give way to a practical quantum computing. As such each vendor has a slightly different approach to the problem.

Atom, for instance, is working on a scalable quantum computing platform that is built around an array of optically-trapped atoms. PsiQuantum, meanwhile is working with GlobalFoundries to adapt silicon photonics to quantum computing to achieve error correction using a lattice of photonic qubits.

Finally, Microsoft, the largest of the three, is in the process of developing a quantum system that uses a topological qubit architecture, which the company says will allow them to shrink a million-qubit system down to the point it can fit in a closet.

For those that aren't familiar, qubits, are the basic unit of computing in quantum systems. However the mechanism by which these qubits are harnessed varies depending on the design.

“The ultimate outcome of the program is a win-win. For US commercial leadership in this strategically important technology area and for national security to avoid being surprised,” Altepeter said.

The US is hardly the only country investing in quantum computing. China is actively developing quantum systems of its own. Earlier this year, a research paper stoked fears that the Chinese were on the verge of breaking 2048-bit RSA encryption.

As we detailed at the time, the paper suggested that applying Claus Peter Schnorr's recent factoring algorithm to a quantum approximate optimization algorithm, one could break RSA-2048 encryption using a system with as few as 372 physical quantum bits.

That’s substantially lower than the 10,000 qubits and 2.23 trillion quantum gates that Fujitsu researchers recently estimated would be required to break RSA encryption in 104 days. As we previously noted, we're a good way away from hitting that mark. IBM's Osprey system has 433 qubits of computation power.

And while researchers disagree on the credibility of the paper’s conclusions, the potential for quantum computing to disrupt governments clearly hasn’t gone unnoticed, especially as US-China relations continue to deteriorate. ®