Axions require proof: new sensors will help extract energy from dark matter

Russian researchers have created sensors for astrophysics that are two to three times more sensitive than their global counterparts. The devices will allow us to study the processes that took place at the early stages of the evolution of the Universe, as well as to search for axions, theoretical particles that are considered as one of the possible components of dark matter. According to one hypothesis, axions can transform into photons, particles of electromagnetic radiation, under the influence of a magnetic field. In the future, the energy of this process can become an almost inexhaustible source. At the same time, experts note that dark matter may not be a collection of particles, but a property of space itself.

How scientists achieved high sensitivity of sensors

Scientists from the Institute of Physics of Microstructures of the Russian Academy of Sciences and the R.E. Alekseev Nizhny Novgorod State Technical University have created sensors for radio astronomy, the sensitivity of which is two to three times higher than that of known world analogues. A patent of the Russian Federation was obtained for the development.

— In fact, detectors are receivers of electromagnetic radiation. When it hits the sensor element, the temperature of the electrons increases, which leads to a change in the recorded signal. At the same time, it is important to minimize heat leakage as much as possible, since the useful signal is lost along with it," Andrei Pankratov, a leading researcher at IFM RAS and NSTU, explained to Izvestia.

According to him, this was achieved thanks to a thin layer of hafnium in the structure. It acts as a thermal barrier, slowing down the transfer of electron energy to the environment and reducing stray currents, which increases the sensitivity of the sensor.

The new devices will expand the possibilities of radio astronomy research. In particular, they can be used to study cosmic microwave background radiation, a weak microwave background that evenly fills the universe. His research allows us to obtain data on the processes that took place in the early stages of its evolution after the Big Bang.

In addition, detectors can be used to search for axions, hypothetical particles that are considered as one of the possible components of dark matter, an invisible substance that makes up a significant part of the mass of the universe, but the nature of which remains unknown.

— It is believed that axions almost do not interact with ordinary matter, so it is extremely difficult to detect them directly. But under the influence of a strong magnetic field, they can turn into photons, particles of electromagnetic radiation that the sensor can register," said Andrey Pankratov.

Energy Vector: solar-powered ambulance and new 3D printing technologies

Izvestia has collected the top 5 science news for the week

How to get a new inexhaustible source of energy

According to the scientist, dark matter can potentially become a source of almost inexhaustible energy. If the existence of axions can be confirmed and we can learn how to control their conversion into photons, the resulting radiation can theoretically be converted into electricity. Since, according to modern concepts, dark matter is present almost everywhere, the reserves of such a resource in the universe can be huge. In the future, this energy could be used both on Earth and on spacecraft for long-range expeditions and flights to other star systems.

— It is more correct to speak not about the "energy of dark matter", but about the energy of electromagnetic radiation, which can be converted from dark matter. So far, this is only a promising scientific hypothesis. But the new sensors, due to their high sensitivity to weak electromagnetic signals, can become one of the tools for testing it," the scientist said.

In his opinion, the new devices can also be used as backup receivers for the promising Millimetron space observatory and ground-based astrophysical complexes. In particular, such radio telescopes are planned to be placed on Mount Hulugaisha in the Eastern Sayan Mountains, in Buryatia.

The site is located at an altitude of about 2.8 thousand m. Interest in it is primarily due to the low content of water vapor in the atmosphere: it absorbs millimeter and submillimeter radiation.

— The new sensors use effects that have not yet been described by theory. In a sense, they have outstripped it, which opens up the possibility for a number of groundbreaking experiments at the cutting edge of science. At the same time, the uniqueness of the detectors lies not only in their record sensitivity, but also in their ability to register not individual signals, but to accumulate their statistics. This will help us understand the nature of radiation from astrophysical objects and study the processes taking place inside them," Professor Vasily Stolyarov, director of the Center for Advanced Methods of Mesophysics and Nanotechnology at MIPT, told Izvestia.

In his opinion, such detectors can help identify previously unidentified signals against the background of noise, including those related to the near-Earth environment. At the same time, the patent for the device indicates that the development has not only fundamental, but also applied significance and is potentially ready for production.

Among the possible difficulties, the expert mentioned the complexity and high cost of manufacturing superconductors at the current stage of scientific development. In addition, the devices require cooling to several tens of millikelvins to operate. However, the development of technology and the improvement of technology gradually make it possible to overcome these limitations.

— Now, when many foreign technologies are unavailable, the creation of our own sensors of this class for domestic science is not only a matter of prestige, but also a vital necessity. They will ensure the technological independence of national scientific projects," says Vladimir Afanasyev, an astrophysicist and science popularizer.

At the same time, in his opinion, the hypothesis of axions as a source of practically inexhaustible energy should be treated with caution. Initially, the existence of these particles was assumed to explain the baryon asymmetry of the universe, a mystery related to why there was significantly more matter than antimatter after the Big Bang. At the same time, dark matter and dark energy are different physical concepts: the latter can be considered as a property of space itself. Nevertheless, the confirmation or refutation of the existence of axions will be a significant result for science, the expert concluded.