Massive Microsoft Quantum Computer Breakthrough Uses New State Of Matter

Microsoft announced this morning that it has invented an entirely new kind of quantum computer. Its new quantum chip, Majorana 1, is a quantum processor analogous to transistors in classical computers’ semiconductor chips and offers a path to million-qubit systems in a single relatively small quantum computing fridge. Intriguingly, Microsoft essentially created a new state of matter, a topological superconductor, to make this happen. Most importantly, Microsoft believes that this development, 19 years in the making, will enable the construction of commercially usable and viable quantum computers this decade: within five years.

“We’ll have a fault tolerant quantum computer, a real fault tolerant quantum computer in years, not decades,” says Dr. Chetan Nayak, who runs the quantum hardware program at Microsoft and has been working on this problem for almost two decades. “And once we have that, that’s the thing we’re going to build on to get out to utility scale.”

Microsoft has already built an eight-qubit proof of concept, which it has submitted to the Defense Advanced Research Projects Agency (DARPA) and has resulted in the company’s inclusion in DARPA’s final phase of the Underexplored Systems for Utility-Scale Quantum Computing (US2QC) program.

There’s a lot to break down in Microsoft’s announcement. Essentially, Dr. Nayak told me in a TechFirst podcast, it relies on four key breakthroughs:

1. An entirely new state of matter: a topological superconductor
2. A means of measuring quantum states non-destructively
3. A way to load data into these qubits
4. A way to make multi-qubit structures

Superconductivity is a state of matter, Nayak says, as much as liquid, gas, solid, or plasma. Topological superconductors, which Microsoft doesn’t believe occurs naturally in the universe, are composed of a materials stack including indium arsenide, aluminum, and other materials, most of which Microsoft fabricated atom by atom.

The elements for the topological superconductor are then cooled to 50 millikelvins. That’s colder than outer space: -273.15 degrees Celcius or -459.58 degrees Fahrenheit.

The special thing about topological superconductors is that they are perfectly fine with possessing uneven numbers of electrons, unlike any other kind of superconductor. Microsoft found a way to “hide” these odd-man-out single electrons on nano-scale wires forming Majorana zero modes. Essentially, instead of storing quantum information in a single particle, a Majorana-based qubit has two of these tiny wires and four Majorana zero modes.

The Microsoft found a way to non-destructively measure the existence of this single electron in microseconds, and change the orientation of the Majorana zero modes. That enables storing data in these topological superconductor qubits and reading it. The good news is that these quantum states are relatively long-lived, for quantum events, lasting whole milliseconds: a long time at the quantum scale. Using a quantum dot, Microsoft can measure them in microseconds, resulting in an essentially stable element of a quantum computing “chip.”

Critical to Microsoft’s goals, however, was to make a relatively small quantum processing chip.

“If you don’t have a fairly small quantum processing chip, then you are not going to put it in a single fridge,” says Nayak. “You are necessarily networking multiple fridges and then you’re not only solving the problem of building a quantum processor at scale, you’re also have to solving the quantum networking challenge … so you have to solve two super difficult problems.”

The easier solution, Microsoft says, was to build a qubit processor that is relatively: small enough to fit a million qubits in a single fridge-sized quantum computer.

“If a single million qubit quantum computer is an entire data center, it’s some huge machine networked between multiple fridges,” Nayak says. “And then you need a thousand of those data centers, then it looks really hard, right?”

Ultimately, that’s what Nayak sees: the need to have at least 1,000 of these million-qubit quantum computers. The massive breakthrough now is that Microsoft actually sees a path to manufacturability of these topological superconductor quantum computers.

But it’s been a long time coming.

In fact, this is the single longest-running R&D program in Microsoft’s history: 19 and a half years over multiple CEOs, multiple chains of command, and multiple bosses since Nayak joined to work on this problem in 2005. Over 160 researchers, scientists, and engineers have their names on the paper that Microsoft has published on this new type of qubit, and Nayak says that’s not just due to politeness.

The challenge scope was immense. Just like scientists and engineers had to invent transistors for the computers of the mid-20th century, Microsoft believed it needed to invent essentially quantum transistors for a scalable quantum computer.

“Whatever you’re doing in the quantum space needs to have a path to a million qubits. If it doesn’t, you’re going to hit a wall before you get to the scale at which you can solve the really important problems that motivate us,” Nayak said. “We have actually worked out a path to a million.”

Interestingly, Microsoft’s this-decade timeline aligns with several other quantum competitors’ timelines for usable quantum computers.

“We are focusing on quantum simulations, optimization, and quantum machine learning to achieve quantum advantage from 2027,” says Jan Goetz, CEO & co-founder at IQM Quantum Computers.

And Dr Chris Ballance, co-founder and CEO of Oxford Ionics, thinks he’ll have 200-qubit systems in customers hands within the next two years.

A million qubits however: that’s another matter indeed.

“All the world’s current computers operating together can’t do what a one-
million-qubit quantum computer will be able to do,” Microsoft says.