Even as of July 2021, Majorana modes were elusive.

In fact, in March of 2021 Nature had published a retraction of an earlier paper that had claimed to have found the elusive particle.

The Majorana fermion, a particle that is its own antiparticle, is the brainchild of Italian theoretical physicist Ettore Majorana. It is not a discrete particle but a quasiparticle and consists of two paired electrons. The pair exist in two energy states as well as in a superposition state, just like “qubits” that consist of electrons or photons.

Originally, Majorana zero modes were simply a mathematical construction that allowed an electron to be described theoretically as being composed of two halves. From a quantum computing perspective, they are attractive because if an electron can be “split” into two, the information it encodes as a qubit will be protected from local perturbations as long as the “half-electrons” can be stored far away from each other. “This concept is not so different from what Voldermort did in Harry Potter to protect his soul,” Katsaros explains. “He split into several horcruxes his Majorana zero modes.”

In fact, there is a checklist to confirm the claim for the determine the presence and extent of a topological phase with Majorana zero modes.

4 days ago, on March 14, Microsoft announced:

The Azure Quantum team has engineered devices that allow them to induce a topological phase of matter bookended by a pair of Majorana zero modes. These quantum excitations don’t normally exist in nature and must be coaxed into appearing under incredibly precise conditions.

The ability to create and sustain a quantum phase with Majorana zero modes and a measurable topological gap removes the biggest obstacle to producing a unique type of qubit, which Microsoft’s quantum machine will use to store and compute information, called a topological qubit. It’s the foundation for Microsoft’s approach to building a quantum computer that is expected to be more stable than machines built with other types of known qubits, and therefore scale like no other.

Topological qubits are expected to be faster, smaller and less prone to losing information than other types of qubits currently under development. Microsoft believes creating a more stable topological qubit is the clearest and fastest path to building an industrial-scale quantum machine.

---

While there is still some wait before this research makes its way into a button click on the browser — to spin up a Quantum instance with possibly millions of qubits on Azure (btw, you can spin up quantum instances on most major cloud platforms today including Azure), I still find it fantastic that we will potentially be running our computations on our hypothesised understanding of the elementary building blocks of nature itself! Amazing science, amazing tech!