Microsoft, Google, and Amazon's Quantum Launches
Chapter 1 of the Quantum Computing Series. Discussion about what progress big companies are really making in this field, and the state of quantum computing, with Joel Pendleton of Conductor Quantum
About the Quantum Computing Series
Understanding quantum computing requires understanding multiple disciplines. That’s why I’m so drawn to write about this topic, but also why I like to invite experts to the discussion. In this chapter, I talk to Joel Pendleton, who withdrew his Oxford PhD to build Conductor Quantum - a company creating quantum computers on silicon chips.
Enjoy the reading & see the complete Quantum Computing Series listed at the conclusion of this post.
Microsoft, Google, and Amazon’s Quantum Launches
A few weeks ago Microsoft released what’s supposed to be a “big breakthrough” in quantum computing, and their CEO, Satya Nadella, even tweeted about creating “an entirely new state of matter”.
Microsoft has been working on a specific type, different from what Google or other companies are doing. It’s called topological quantum computing, and it uses special types of quasiparticles. The quasiparticles form braids, which are then used to realize the qubits (instead of single particles, like in other types of quantum computers). The braids have the advantage of being more stable than particles in other types of quantum computers.
What Microsoft just announced is that they have Majorana 1: the world’s first Quantum Processing Unit (QPU), or a quantum chip in other words, powered by a topological conductor. In particular, they announced the detection of Majorana fermions, something like building blocks they plan to use for topological qubits.
They announced our ability to harness a new type of material and engineer a radically different type of qubit - that’s what they published in Nature. A well-known theoretical physicist published a pre-print critique that argues Microsoft’s work “is not reliable and must be revisited.” Other scientists argued the same or called the announcement a “distraction”.
Shortly before the Microsoft announcement, Google also made its own launch. They introduced Willow, a new quantum chip. What makes Willow special is the ability to reduce errors exponentially the more qubits are used. This seems very counterintuitive. When adding more qubits to a quantum system, you would expect more errors to occur because each additional qubit brings its own potential for errors. Willow demonstrates the opposite behavior, and as their team says, it cracks the challenge of quantum error correction that the field has pursued for almost 30 years.
Another tech giant, Amazon, also recently announced a new quantum computing chip. Their new 'Ocelot' chip has a special architecture for reducing error correction by up to 90% and accelerating the development of real-world quantum computing applications.
The diagram below provides a crucial visual perspective on the quantum computing landscape by plotting error rates against qubit counts.
Looking at current companies like Google, IBM, Rigetti, and others, they are operating with relatively high error rates (10^-2 to 10^-1) and modest qubit counts (under 100).
Reading
Microsoft’s Majorana 1 chip carves new path for quantum computing by Microsoft
Tweet commenting the Microsoft quantum breakthrough by Satya Nadella, CEO of Microsoft, with additional community comments
Amazon Web Services announces a new quantum computing chip by Amazon
Quantum Error Correction: An Introductory Guide by Joschka Roffe
Discussion with Joel
Let’s talk about the whole Microsoft launch. Of course, people speculate how much of this is just a strong PR. What do people from the quantum computing field think about Microsoft’s launch?
The quantum computing community is generally skeptical of Microsoft's claims. Many insiders know that Microsoft had previous credibility issues in this field—they announced a discovery years ago that was later proven false. This incident damaged reputations, with some prominent researchers losing standing in the scientific community, yet some still work at Microsoft.
Physicist Henry Legg has published a rebuttal to Microsoft's current claims, pointing out methodological issues. Even the review comments for the Nature paper don't clearly validate Microsoft's results—there's a sense the paper might have been accepted more for its potential than solid evidence.
And there's a big difference between what the CEO of Microsoft said publicly and what the researchers of Microsoft claimed. I'm not saying it's bad science. I'm just saying the media took it a bit further than it probably did.
Let's say it's not a "huge breakthrough" then, but it can still be a smaller breakthrough, right? What is safe to say about what Microsoft has at this moment?
Microsoft isn't necessarily close to having a working quantum computer. What they've demonstrated is a method to potentially measure Majorana fermions through a topological conductor—a capability they previously lacked. This is a huge step forward, but Microsoft is likely years away from a functional quantum computer.
The challenge isn't just detecting Majorana fermions once—you need to reliably read many of them, perform operations on them, and scale the entire system. Each of these steps presents significant scientific and engineering obstacles.
So they now claim to have a topological conductor that helps them read Majorana's fermions. Which they weren’t able to make before if I understand correctly. What is the challenge in reading Majorana fermions?
Yes, Microsoft is now able to confirm the presence of Majorana fermions - exotic quasiparticles that exist at the ends of special nanowires. Unlike regular fermions (like electrons) that are distinct from their antiparticles, Majorana fermions are their own antiparticles. In Microsoft's approach, these quasiparticles would form the basis of topological qubits, which is just one of several ways to build quantum computers.
Other quantum approaches use different physical systems for qubits: superconducting circuits (IBM, Google), trapped ions (IonQ), or electron spins (an approach we have at Conductor Quantum).
Topological quantum computing has many advantages, but on the other hand, reading Majorana fermions is a particularly difficult challenge. It’s because they're not simple particles but emergent properties of a complex quantum system. Even confirming their existence requires precise measurements and careful elimination of alternative explanations.
This detection capability is just the first step. For a working quantum computer, Microsoft would need to reliably create, read, and manipulate many Majorana fermions, and then scale the entire system. Each of these challenges represents significant scientific and engineering hurdles.
The topological quantum computing Microsoft is working on has the potential to reduce errors. Why are no other big players building these? Are there tradeoffs in other aspects? What are other challenges apart from reading the Majorana fermions?
I would say, with a topological quantum computing approach, Microsoft is at a similar stage of making qubits that other quantum computing types were twenty years ago. Topological quantum computers are still in the early research and development phase, compared to other types.
That's not to say it's not cool, I think the science behind this is really great if it's true. Microsoft’s paper claims that they have a high probability of being in the topological phase.
So do you think they really might have the topological conductor soon in the future?
Maybe they have their hands on that. The problem is, that Microsoft hasn't established clear metrics or validation methods for their protocol. This methodological gap is why Henry Legg and many specialists in Majorana physics remain unconvinced. The scientific community is especially skeptical given Microsoft's history. While there's always a possibility this represents a genuine breakthrough, most experts are approaching it with caution.
People speculate the reason for this timing of Microsoft’s paper is that Google made the announcement of Willow, the new quantum chip a few weeks prior. Can we talk about this release? What they launched, how big news is that?
I'd say that what Google released was actually a huge breakthrough. This is not just because of the number of qubits they have but because the Google team uses really good calibration software that allows them to control these qubits and allow for large-scale error correction. (Calibration refers to fine-tuning and adjusting the quantum computer's components to ensure they operate correctly and with minimal errors.)
Part of Microsoft’s news was also saying that they are now able to make much smaller qubits and much faster ones. I don't understand how the topological conductor makes the qubits be smaller or faster. How does this work?
Microsoft's claims about "smaller" qubits refer to physical size advantages. Their approach combines semiconductor and superconductor layers in nanoscale devices that are much smaller than trapped ion or neutral atom systems. While ions require vacuum chambers and laser systems, Microsoft's solid-state approach potentially allows for more compact hardware.
The "faster" claim relates to interaction speed. Smaller quantum systems generally allow for faster operations because they can interact more quickly with control signals. The fundamental tradeoff in quantum systems is that a smaller size typically means more noise sensitivity. But here's where Microsoft's approach is clever—topological qubits theoretically maintain the speed benefits of small systems while eliminating their typical noise vulnerability through topological protection.
Regardless of the skepticism, this combination—if it works—would be revolutionary. While we want to see it succeed, their approach remains largely theoretical while other technologies like the spin qubits we work withmake at our company, Conductor Quantum, are already operational. The quantum computing race is a marathon, not a sprint. Many well-funded companies will emerge, but the winners will be those focusing on solid science and practical applications rather than hype.
I didn't know the past problems of Microsoft’s academic work were that serious. Still, it’s interesting to know the theory behind this approach to quantum computing, and I guess we can just hope for big future progress.
In the longer term—twenty or thirty years—this could potentially be a viable approach to quantum computing if their claims hold up. However, researchers are already identifying potential flaws in their measurement techniques and readout interpretations.
Despite my skepticism, I genuinely hope they've made a real discovery. A new pathway to quantum computing would benefit everyone in the field, and the theoretical foundation of topological quantum computing remains mathematically beautiful.
Read more of the Quantum Computing Series:
Chapter 1: Microsoft And Google's Quantum Launches
Chapter 2: Building a Quantum Computer
Chapter 3: Types of Quantum Computers
Chapter 4: Quantum Computers Market Landscape
Chapter 5: Topological Quantum Computers Explained
Resources to start with quantum computing
What Quantum Computing Isn't by Scott Aaronson
Learn the Algorithms Behind Quantum Computing by Beau Carnes
Landscape of Quantum Computing in 2024 by Samuel Jaques
Quantum Computing on Wikipedia