Building a quantum computer has always been difficult. It just gets more difficult.

Phil Morle, a partner at CSIRO’s Main Sequence Ventures fund who specializes in this type of investment, said what happened to SQC was typical of what was happening across the industry: investments were “split” into smaller rounds with shorter, more demanding time frames.

“There’s a kind of hyper-dynamic going on in investments… where there’s more caution and more expectation of early revenue proof. That is something deep tech companies need to pay close attention to,” he said.

“A few years ago, we could have put together a longer-term plan to push the technology to commercial outcomes a little later, but that is no longer on the table today.”

Professor Simmons said the change in investor expectations has led to a re-adjustment at SQC, both in terms of growth rate – if $150 million is raised, there will be “more ambition to expand the company”. company faster” – and in terms of the technology it is focusing on.

The company now talks about quantum simulation, as opposed to quantum computing, more than it did before.

Professor Simmons said: “I think ultimately everyone wants a programmable computer, but on the way to getting there, everyone realizes that the commercial products of the near future are more likely to appear more in the simulation space”. AFR weekend.

Fortunately, it turns out that SQC’s plan to build a quantum computer, first proposed by American physicist Bruce Kane when he visited UNSW as a student in 1998, is also “exceptional”. consistent with quantum simulations, she added.

Kane’s ambitious plan is to put phosphorus atoms on a silicon chip, arranging them with such precision that they can interact with each other to form a quantum computer.

The plan – if SQC pulls it off – would mean a quantum computer with more qubits than any other computer. Each of SQC’s qubits is just one atom in size, where competitors like Google and Microsoft are making qubits from superconducting circuits that, while tiny, are measured in tenths of a millimeter, rather than tenths of a nanometer. .

About 25 years on, Professor Simmons said, SQC has developed that atomic alignment technology to the point where the company can now launch new experimental versions of its quantum computer every week, while also advancing to build an error-correcting quantum computer by 2033.

Error correction, which largely involves gluing dozens or hundreds of physical qubits together to form a single “logical” qubit, is how the industry addresses the problem of turbulence.

In theory, a stray cosmic ray could disrupt a physical qubit, but it wouldn’t be enough to eliminate an entire logical qubit.

SQC’s most recently revised roadmap calls for it to deliver a single, error-correcting qubit made up of 100 physical qubits by 2028. By 2033, it is building an error-correcting computer powerful enough to “ useful” for “many audiences”. users in many use cases.

(The roadmap has changed over the years. Professor Simmons initially hoped to build a 10-qubit quantum computer prototype by 2020, but later revised that date to 2023. Although SQC is still working on track to produce such a prototype this year, but that’s what she said, the bug-fixed milestone that’s now a major one.)

The rapid iteration takes them to an error-correcting quantum computer that also works well for quantum simulations. Etching a molecular model onto silicon to perform a single calculation is not difficult when you can create new models on the fly.

“Our approach translates unusually (or exceptionally) well to simulation. We produce the equipment quickly – within a week,” she said.

Even so, Simmons said revenue from easier quantum simulation technology is still “three to five years away.”

Whether that will be fast enough for investors, only time will tell. However, with a number of quantum computing startups already putting revenue on the books, the pressure on SQC to generate revenue has only increased over the past 12 months, making its task more difficult ever.

Q-CTRL, a quantum computing startup at the University of Sydney that produces error correction software for quantum systems including quantum computers, has announced $15 million in revenue in 2022 and be cash flow positive in the first half of 2023, founder Michael Biercuk said.

He added that almost all of the $54 million that Q-CTRL raised this year in its Series B fundraising is still in the bank.

“Investors are no longer saying ‘Oh my God, one day quantum computing will be ubiquitous, but who knows when?’ That’s no longer a conversation,” said Main Sequence’s Morle, whose fund invested in Q-CTRL.

“Quantum computing is now fully commercialized and investors are starting to look at it through that lens.”