Scientists at Princeton University used a scanning tunneling microscope to show the atomic structure of an iron wire into an atom wide on a lead surface. The enlarged portion of the image shows the quantum probability of the content in the wire of an elusive particle called the Majorana fermion. It is important to note that the picture shows particles at the end of the wire, which is exactly where the theoretical calculations predicted for many years.
If you thought that the search for the Higgs boson - the elusive particle that gives matter mass - was epic, then think about the physicists who were trying to find a way to discover another subatomic particle hidden since the 1930s, when the first assumption appeared.
But now, thanks to the use of 2 fantastic large microscopes, this very strange and potentially revolutionary particle has been discovered.
Imagine the Majorana fermion, a particle that is also its own antiparticle, a candidate for dark matter, and a possible mediator of quantum computing.
Fermion Majorana is named after the Italian physicist, Ettore Majorana, who formulated a theory describing this unique particle. In 1937, Majorana predicted that a stable particle can exist in nature, which is both matter and antimatter. In our everyday experience there is also matter (which is found in abundance in our Universe) and antimatter (which is extremely rare). If matter and antimatter meet, they annihilate, disappearing in a flash of energy. One of the biggest mysteries of modern physics is how the Universe became more matter than antimatter. Logic dictates that matter and antimatter are parts of the same thing, like opposing sides of a coin, and should have been created at the same pace. In this case, the universe would have been destroyed before it could establish itself. However, some process after the Big Bang shows that more matter was produced than antimatter, so it is important that matter won, which fills the Universe that we know and love today.
However, the Majorana fermion is different in its properties and is also an antiparticle. While the electron is matter, and the positron is the anti-material particle of the electron, the Majorana fermion is both matter and antimatter. It is this material / anti-material duality that has made this little beast so difficult to trace over the past 8 years. But the physicists did, and in order to accomplish the task, it took tremendous ingenuity and an enormously large microscope.
The theory shows that the Majorana fermion should extend on the edge of other materials. Thus, a team of Princeton University created an iron wire into an atom thick on the lead surface and made an increase at the end of the wire using a mega-microscope in the laboratory of ultra-low vibrations at Yadwin Hall in Princeton.
“This is the easiest way to see the Majorana fermion, which is expected to be created on the edge of some materials,” says leading physicist Ali Yazdani from Princeton University, New Jersey, in a press release. "If you want to find this particle inside the material, you must use a microscope that allows you to see where it really is." Yazdani's research was published in the journal Science on Thursday (October 2). The search for the fermoion Majorana is significantly different from the search for other subatomic particles that are more illuminated in the wide press. Hunting for the Higgs boson (and similar particles) requires the most powerful accelerators on the planet to generate the enormous energy collision necessary to simulate conditions soon after the Big Bang. This is the only way to isolate the rapidly decaying Higgs boson, and then study the products of its decay.
In contrast, the Majorana fermion can only be detected in a substance by its effect on the atoms and the forces surrounding it - so no powerful accelerators are required, but the use of powerful scanning tunneling microscopes is necessary. Very fine tuning of the target material is also required in order for the Majorana fermion to be isolated and displayed.
This strict control requires extreme cooling of thin iron wires to ensure superconductivity. Superconductivity is achieved when thermal fluctuations of a material are reduced to such an extent that electrons can pass through this material with zero resistance. By reducing the target to 272 degrees Celsius — to one degree above absolute zero, or 1 Kelvin — ideal conditions can be achieved for the formation of the Majorana fermion.
“This shows that this (Majorana) signal exists only on the edge,” said Yazdani. “This is a key signature. If you do not have it, then this signal may exist for other reasons. ” Previous experiments removed possible signals from the Majorana fermion in similar installations, but this is the first time that a particular particle signal has appeared, after removing all sources of interference, exactly in the place where it is predicted to be. “This can only be achieved through an experimental setup — simple and without the use of exotic materials that could interfere,” Yazdani said.
“What is interesting is that it is very simple: it is lead and iron,” he said.
It has now been found that there are some interesting opportunities for several areas of modern physics, engineering and astrophysics.
For example, the Majorana fermion weakly interacts with ordinary matter, as does the ghostly neutrino. Physicists are not sure whether neutrinos have a separate antiparticle, or, like the fermoion of Majorana, is its own antiparticle. Neutrinos abound in the universe, and astronomers often point out that neutrinos are a large part of the dark matter that is thought to fill Cosmos. Probably, neutrinos are the same as particles of Majorana and Fermions. Majorana are also candidates for dark matter.
There is also a potentially revolutionary industrial application if physicists can encode matter with Majorana fermions. Currently, electrons are used in quantum computing, potentially creating computers that can solve previously innumerable systems in an instant. But electrons are notoriously difficult to control, and often violate calculations after interacting with other materials around them. However, the Majorana fermion, which is extremely weakly interacting with the material, is surprisingly stable due to its material / anti-material duality. For these reasons, scientists can use this particle, technically applying it in materials, coding, and, possibly, discovering more and more new methods of quantum computing.
Thus, although its discovery does not create drama and the pushing of relativistic particles together in the vacuum chambers of the LHC detectors, the more subtle discovery of the Majorana can develop a new approach to dark matter and revolutionize computing.
And, perhaps, the 80-year wait for its opening was worth it, after all.