[shalg]

Some background for the unfamiliar. This is a new type of quantum computing platform that Microsoft has been pursuing almost independently. Most major research groups focus on superconducting qubits (IBM, Google) or trapped atoms/ions, (or photonics, or a lot of other things) while Microsoft has been developing topological qubits. These qubits are particularly interesting because they exhibit a natural resilience to noise that all other qubit systems lack. However, creating them has been a major challenge.In the summer of 2022, Microsoft claimed for the first time to have created a such qubit, though their results were met with some skepticism.

Now, it seems there is no longer any debate. Microsoft has successfully created and controlled topological qubits. Is this a big deal? Yes but its a far cry from a million qubits. Fair warning, this is not my area of research, so I'm unsure what developments occurred between their 2022 results and now. The relevant papers from Microsoft can be found here: https://www.nature.com/articles/s41586-024-08445-2 https://arxiv.org/abs/2502.12252

edit:

I read the nature paper more carefully, it looks like it is still up for debate whether they have made a topological qubit, but the evidence today is considerably stronger than previous results. Anyways don't start worrying about microsoft hacking your bank account just yet.

[shalg]

Oh also to clarify: What exactly is the device they have made? Well it's pretty complicated but one handwavey explanation is that they have created a device that splits an electron into two quasiparticles and does computations by physically moving these quasiparticles around each other. This is what they refer to as braiding.