Microsoft, Atom Computing, EeroQ update their quantum computing progress
Source: Ars Technica
Progress Reports
Some quantum computing companies we’ve covered have done recent progress updates.
With dozens of companies—ranging from small startups to tech giants—pursuing quantum computing, there’s a steady flow of results as they try to find a path to utility. We typically focus on new technologies and major landmarks, which can obscure the fact that any big success will inevitably have been built on a lot of incremental progress.
The past few weeks have seen a number of companies release progress reports on how they’re trying to get the technologies closer to general use. None of these represents a major breakthrough, but all are absolutely necessary for the technology to advance. The idea here is to convey the hard work required to move us closer to something useful.
Microsoft and Topological Qubits
Microsoft is one of the few companies pursuing topological qubits, which exploit the exotic physics that emerges when particles are confined to very small dimensions. Their approach uses a thin superconducting wire placed on top of a semiconductor:
- In a superconductor, electrons pair up into Cooper pairs.
- If the wire contains an odd number of conducting electrons (i.e., a single unpaired electron), that electron becomes delocalised to both ends of the wire—a hallmark of the Majorana mode that topological qubits rely on.
From Theory to Experiment
Before building qubits, Microsoft had to verify that this behaviour actually occurs as theorised. The path has been rocky:
| Milestone | Outcome |
|---|---|
| Early experimental claims | Later retracted (see Nature article) |
| Initial devices (Al‑based) | Extremely noisy; parity flipped every ≤ 10 ms |
| Community reaction | Skepticism about the robustness of the observed physics |
Retracted work: Nature – 2021 retraction
Roadmap announcement: Ars Technica – 2025 roadmap
Materials Upgrade – A Significant Leap
In a recent update, Microsoft reported dramatically improved performance after changing the materials used in the qubits:
| Component | Old material | New material | Effect |
|---|---|---|---|
| Superconducting wire | Aluminum (Al) | Lead (Pb) | Reduced noise, longer parity lifetimes |
| Semiconductor | Standard composition | Sn‑doped (tin added) | Enhanced spin‑orbit coupling with Pb |
With the new stack, the parity state—the key observable for topological protection—can now remain stable for up to 20 seconds, compared with the previous sub‑10 ms timescale.
Current Architecture
- Two parallel nanowires form each qubit.
- Parity is read out via quantum dots that couple to the ends of the wires.
- The system still exhibits three possible parity configurations:
- Both wires have an extra electron
- Neither wire has an extra electron
- A mixed state
Remaining Challenges
- Controlled parity manipulation – Demonstrate gate operations that reliably flip or braid parity states.
- Two‑qubit interactions – Implement coupling mechanisms that enable entangling gates.
- Scalable error correction – Design architectures that link many topological qubits while preserving their protection.
If the forthcoming manuscript survives peer review, Microsoft’s materials‑focused bet appears to be paying off, bringing topological qubits a step closer to practical quantum computing.
Any atom will do
Atom Computing is both a Microsoft competitor and a partner, as its hardware is accessible through Microsoft’s Azure Quantum Cloud service. The companies have also worked together to develop the software and protocols needed to perform error correction on Atom’s hardware.
That’s not “hardware” in the typical computing sense. Most of the solid material involves lasers and optical guides; the computation is done using the nuclear spins of atoms held suspended by an array of laser light. Still, Atom is developing something akin to an architecture in which there’s a storage region, an operations zone, and a collection of backup atoms that can be brought in if one of the others is lost. A configuration of lasers called optical tweezers is used to shuffle atoms among these locations.
In a new manuscript, the company shows just how essential having that reserve of spare atoms can be. To hold their state and keep them in the traps, lasers must be used to cool the atoms, which tend to warm up during operations. The cooling is a slow process, but failure to do so leaves the hot atoms able to hop out of the laser traps that hold them in a grid, which obviously introduces errors.
So, Atom had a bit of a catch‑22: it needed to perform operations to do error correction, but those operations made errors more probable.
Its solution was to identify that it could do the measurements needed for error correction in a way that would swap a spare, pre‑cooled atom into a logical qubit. Tests that repeatedly measured the state of a logical qubit (a linked collection of data‑storing and error‑detection qubits) showed this made a big difference. Performing error correction on the logical qubit without swapping in cold atoms caused the probability of an error to rise with each successive measurement. Doing the swap kept the probability roughly constant over time.
That doesn’t mean the error‑corrected qubit was fully stable. Eventually, one of the errors that inevitably occurred couldn’t be recovered from because too many of its individual atoms changed state at once. However, normal error correction could keep some of these logical qubits stable for up to 90 rounds.
Again, that’s not good enough for any sort of sophisticated calculation, but it’s a lot closer than the company was before working out this technique.
Resonating
EeroQ is a startup with a distinct approach to qubits. While many companies use the spin of electrons in quantum‑dot chips because they’re easy to fabricate, EeroQ builds chips that contain tiny pools holding a drop of liquid helium. An electron placed on that drop has nowhere to go—helium repels extra electrons—so the lone electron simply floats on the surface.
The physics behind this is well‑established, but a practical way to interact with the electron has been missing—until now.
New Manuscript
The company recently released a manuscript (arXiv:2509.14506) describing a new chip version that adds a small resonator next to the helium‑filled pool. The resonator couples to the electron’s motion, which is confined by an electric field that prevents the electron from hitting the pool walls. Because the electron’s motional states are quantized, the resonator adopts one of a few discrete states during the experiment, providing a potential building block for a qubit.
This is not yet functional quantum‑computing hardware, but incremental advances like this are essential for any of these technologies to fulfill their promise.
About the Author
John Timmer – Science editor at Ars Technica. He holds a B.A. in Biochemistry from Columbia University and a Ph.D. in Molecular and Cell Biology from UC Berkeley. When he’s not at his keyboard, he can be found cycling or hiking.
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