Microsoft announces its new Majorana 1 quantum chip

The Redmond company has unveiled a chip with a new architecture that, according to its developers, will finally allow quantum computers to solve "useful" problems.

Majorana 1, el chip cuántico con nueva arquitectura presentado por Microsoft. FOTOGRAFÍA: JOHN BRECHER/MICROSOFT

Microsoft announces new Majorana 1 quantum chip, based on so-called topological qubits

The construction was made possible by the discovery of a new material in the class of topoconductors.The discovery, shared in two scientific articles, the first published in Nature and the second on arXiv, will allow the construction of reliable quantum computers with millions of qubits. Currently, the most advanced machines have thousands of qubits. The "topological" approach to quantum computing convinced the Defense Advanced Research Projects Agency (DARPA) to select Microsoft to build a prototype of a fault-resistant quantum computer.

A bit of theory

Unlike classical machines that use bits – values ​​of zeros or ones – to store and manipulate information, quantum computers use qubits. These can take the values ​​zero or one, but also various combinations, by virtue of the “principle of quantum superposition,” one of the fundamental laws of quantum mechanics.

A qubit processor is not only faster or more powerful, but is also capable of performing operations that a traditional one could never carry out. That is the principle of “quantum supremacy.” In 2019, Google confirmed the triumph of its Sycamore processor in solving a complex mathematical problem in just 3 minutes and 20 seconds, ahead of IBM’s Summit, which would take 10,000 years to do so.

Quantum states of qubits are very delicate entities and extremely sensitive to interference, which is why they must be kept as "isolated" from the outside world as possible. For example, by keeping processors at very low temperatures, close to absolute zero. Interference, and in general any operation performed with qubits, introduces a certain probability of error, which can be amplified in the execution of calculations and lead to a completely erroneous result.

Majorana 1, Microsoft's quantum chip

Named after Catania physicist Ettore Majorana, the quantum chip just unveiled by Microsoft differs from others currently being studied and used. Majorana 1 uses topological qubits, a type of qubit that takes advantage of the topological states of matter to store and process information. Topological states have properties particularly suited to the realization of superconductors and for applications in the field of quantum computing.

Compared to conventional qubits, topological qubits are less susceptible to errors caused by environmental "noise," require minimal error correction, and can be controlled digitally. A much larger number of qubits could make a useful processor for real-world applications. Majorana is an example of a qubit-based quantum processor.

"We have reinvented the transistor"

Just as the invention of semiconductors made smartphones possible, topoconductors and Majorana 1 are paving the way for quantum computers that scale up to a million qubits. We took a step back and said, ‘Let’s try to reinvent the transistor for the quantum age,’” explains Microsoft researcher Chetan Nayak. To do this, the researchers developed a set of materials from scratch, composed of indium aluminum arsenide, designed and manufactured atom by atom to minimize defects. They then tested the chip with a test that consisted of measuring the quantum capacitance of a dot attached to a ‘nanowire’; that is, the chip proved to be sensitive enough to detect the difference between a billion electrons and a billion and one electrons in a conducting wire.

Microsoft has a plan for the future: to build a prototype of an error-resistant quantum computer within a few years, and then develop machines capable of solving real problems. Some practical effects include: designing self-healing materials, sustainable agriculture, and the discovery of safer chemicals. Or designing the architecture of the next generation of quantum computers, which are even more powerful and efficient.

WIRED

Article originally published in WIRED Italia. Adapted by Alondra Flores.