Majorana: Quantum computers and the path to a million qubits

What if I told you that a single computer could single handedly solve many of the worlds modern problems. This computer could accelerate advancements in medicine leading to the development of new drugs, saving millions of lives, it could optimise trade and resource allocation around the world ensuring nothing goes to waste, it can propel research in every scientific discipline leading to new discoveries that can change the way we see the world and much more that I have not mentioned. All this from a single computer, more accurately a quantum computer. But what is a quantum computer and how are we closer than ever to achieving one?

A quantum computer behaves similarly to your classical computer in the fact that it is comprised of bits that can take two values, zero or one. Where we use the bits to store information about something that we care about and this information can read in terms of binary by computers and a wide operations can be performed starting from this, however, that’s where the similarities end. A regular computers has bits that can either take a zero or one with no in between, but a quantum computer uses a quantum bit (qubit), this qubit can not only take a value of zero or one, but it can take these values at the same time. This is called a “superposition” between the two possibilities, and according to quantum mechanics these qubits can be “entangled” by interacting them with each other. What this means, if you were to entangle two qubits they would be in a superposition of all possible combinations of zeros and ones that you could have at once. Scaling this up to millions of qubits, you would have all the possible combinations at once, this make performing computations drastically faster than with a typical computer.

There is a catch to this, for the system of qubits to remain in superposition it must not interact with its surroundings, if it does interact with anything, the system will “collapse” into a single combination and no longer be in a superposition like we want. so what are these “surroundings” that I’m referring to? Anything at all! It could be an electron, an atom, even a light ray. This makes the system highly sensitive, which is a massive problem if you’re looking to scale up to more qubits, since it gets more sensitive the larger the system. Because if even one qubit interacts with something else, it will collapse the entire system of qubits.

This is where the breakthrough at Microsoft with their development of the first-ever topological quantum chip, known as Majorana 1, comes in. Why is this important? It’s because this new quantum chip directly attempts to solve the primary problem of qubits being sensitive to their environment, while not sacrificing any computational power in return. This is achieved using a topological superconductor, which creates a space for quasi-particles to manifest, such as the Majorana particle that was theorized by Ettore Majorana in 1937. These particles will act as the qubits. Now, that was a lot of jargon, but the upshot is that these quasi-particles have differing properties from those you would get from normal qubits. A consequence of this is that as you scale up this new system of qubits, if a qubit interacts with its environment, it does not cause the system to collapse completely, making the system far less sensitive. This single difference alone makes scaling up to a million qubits feasible, as depicted by the image above, where there are many levels that check for errors in the qubits, which can be corrected accordingly.

This breakthrough by Microsoft is promising; however, there has been skepticism of their recent success, and it has been regarded as potentially just “hype.” There have been debates as to whether or not the quasi-particles created are, in fact, Majorana particles, and that further investigation needs to be carried out to confirm this—some going as far as claiming that their test for Majorana particles is “flawed.” Not only that, but despite seemingly solving a major logistical challenge of scalability, new issues present themselves in the form of potential material defects, which could affect the feasibility of making larger quantum topological chips with more qubits. However, Microsoft has prepared and is carrying out a plan to negate this issue. But ultimately, their findings and results do present another tantalizing path, making us closer than ever to achieving a fully usable quantum computer.

Sources:

[1] https://azure.microsoft.com/en-us/blog/quantum/2025/02/19/microsoft-unveils-majorana-1-the-worlds-first-quantum-processor-powered-by-topological-qubits/

[2] https://news.microsoft.com/source/features/innovation/microsofts-majorana-1-chip-carves-new-path-for-quantum-computing/

[3] https://blog.mi.hdm-stuttgart.de/index.php/2024/07/26/importance-and-impact-of-quantum-safe-encryption-for-enterprises/

[4] https://www.ibm.com/think/topics/quantum-computing

[5] https://thequantuminsider.com/2025/02/19/microsofts-majorana-topological-chip-an-advance-17-years-in-the-making/

[6] https://thequantuminsider.com/2025/03/10/major-debate-continues-to-swirl-around-majorana-findings/