If it depends on Microsoft, February 19, 2025 may be considered a milestone in the history of quantum computing. On that day, the Redmond giant presented to the world the first quantum chip with a new topological nucleus architecture, o Majorana 1.
Unlike the classic silicon chips we know, the new processor is based on Qubits. This means that instead of operating with bits (0 or 1), the new processor uses the fundamental unit of quantum computing, which may be in a state overlap, that is, 0 and 1 at the same time.
But the company goes beyond, and states that the quantum chip “which can observe and control Majorana particles to produce more reliable and scalable quibits,” according to a press release.
Presented as “Another phase of the subject that many experts did not find possible”This innovative material can, in theory, be used to solve mathematical, scientific and technological problems.
First theorized in 1937 by the Italian physicist Ettore Majorana, these particles are a special type of fermion that acts as their own antimatter, that is, if two of them met, they could annihilate.
Although never directly observed in nature, these supposed fundamental blocks of matter function as if you look in the mirror and, instead of seeing an inverted reflex, saw exactly the same thing.
This exotic feature makes Majorana’s fermons the ideal theoretical basis for the creation of topological quibits. In practice, quantum information is spread among pairs of identical quasiparticles, becoming less vulnerable to external disturbances.
After all, did Microsoft really create a new state of matter?
Although the term “fourth state of matter”, quoted by Bill Gates’s company, has a certain scientific basis in condensed matter physics, it is another way of highlighting the importance of the discovery in an impactful way.
By announcing a so far unknown state of the matter, Microsoft wanted the announcement to sound great, suggesting a new scientific paradigm, as occurred in 1928, when plasma was recognized as a fundamental state of matter, besides the three classics.
It is not, therefore, solid, liquid, gas or plasma, but of a new emerging state based on topological properties of matter. The company specifically mentions such Majorana fermons, which show exotic behavior to create more stable quibits.
Of course, we could question: But how does a hypothesis in particle physics already have concrete applications in quantum computing?
When he made his unique bet to develop topological quibits almost 20 years ago, Microsoft knew that, in the case of Majorana’s fermons, it would have to work with quasiparticles, that is, collective effects that behave as particles within certain materials.
In this sense, the quasiparticles (such as Fonons, Polarons, Magnons) do not exist independently in vacuum, But they arise within certain materialsdue to the interaction between its components. Although they look like “illusions,” they behave like real particles.
Microsoft confirms two important advances: the creation of Majorana Quasiparticles within a specially designed material and the possibility of reading the data stored in them without destroying the quantum state.
The Great Quantum Computing Race
Since the 1980s ,. The purpose of this powerful machine is not to replace our classic computers, but to solve very specific problems with its high computing power.
For possible advances in medicine, chemistry, material science and other fields, private industry and governments around the world are in a real race to build the first fully functional quantum computer on a real scale.
But the first step to this is to develop stable and scalable quantum processors, quantum chips. They are composed of many quibits. These are physical systems that use peculiar properties of the world of subatomic particles to store and process information.
Unlike Microsoft, which bet on topological quibits with Majorana’s fermons, companies such as IBM, Google and Amazon are testing quibits based on electrical circuits made of superconducting materials, with “pairs of cooper”, electrons that do not act as individual particles.
Ionq and Honeywell, in turn, work with trapped ions, which use these loaded atoms, suspended by electromagnetic fields, to store quantum information at electron energies levels.
California Psiquantum Research QuBits based on photon for use in quantum communications, while Intel and Qutech exploit silicon quibits that operate based on the spin from a single electron confined to a semiconductor material.
In search of the ideal quantum chip, the important thing is not the amount of quibits (so much so that Microsoft has only produced eight topological quibits so far), but the quality of quibits.
Why is it so difficult to build a quality qubit?
In search of a “logical qubit”, all the researchers were able to produce were imperfect or low quality quibits. But everyone agrees that this holy grail of quantum computing would be protected against errors and with a very high fidelity.
Last year, when Google presented its Willow Quantum Processor, designed to use logical quibs instead of just physical quibits, the idea was that, increasing the number of quibits, it could exponentially reduce the number of errors.
Following the same path, Microsoft seeks to correct errors, but in a less complex and more efficient way with its Majorana 1, if it can improve its topological quibits, several scientists say.
Although all these quibits can store multiple values at the same time, they all face a fundamental limitation. When researchers try to read the information they store ,.
In other words, if you try to read a qubit, it immediately loses your superpower. Therefore, this is the big fundamental problem that researchers have to solve: How to build a quantum computer if it destabilizes each time it is used?
“Ironically, that’s why we also need a quantum computer,” explains Microsoft senior technical expert Krysta Svore. Only with the machine on scale, it would be possible to predict materials with better properties, concludes the expert in her paradox.
