“A research team from ITMO University has devised a metamaterial that may be used to investigate the properties of axions, also known as dark matter candidates. The paper was co-authored by Frank Wilczek, a laureate of the Nobel Prize in Physics, and published in Physical Review B.
Dark matter is one of the greatest unsolved mysteries in physics, with even its structure unknown to scientists to this day. One hypothesis is that dark matter is made up of axions, hypothetical particles predicted by Frank Wilczek, a Nobel Prize-winning physicist, in the 1970s. Axions exhibit a weak interaction with ordinary matter and can convert to photons in a strong magnetic field.
While some researchers are trying to trace down axions in space or on Earth, others are studying the particles using models, like metamaterials. These are artificially engineered substances with extraordinary mechanical or electromagnetic properties that derive their properties from both their structure and chemical composition.
Since some metamaterial quasiparticles – collective excitations of light and matter – can be described by the same equations as axions, researchers opted for artificial materials to build a platform for investigating axion physics phenomena.
Even though similar systems exist in solid-state physics, they have a weak axion response. Therefore, scientists from ITMO’s Frontier Laboratory “Probing fundamental physics with topological metamaterials” and Frank Wilczek proposed to create a photonic metamaterial with enhanced axion effects.
The novel substance is an assembly of layers with well-studied magnetic and optical properties. Quasiparticles in a metamaterial exhibit the same properties as hypothetical axions, which has been proved by several experiments.
Because of its distinct structure, the metamaterial can regulate an axion response, which has no analog among natural materials studied by solid-state physics.
The team proposed new tools and ideas for axion studies, which might be of use in pursuit of dark matter particles. In the meantime, the researchers plan to examine other “exotic” responses in metamaterials.
The team’s optimism is justified: alongside their research, they are taking part in an international consortium on the search for space axions.
The study is supported by the Russian Science Foundation and ITMO’s 2030 Development Strategy. “