An international team of researchers has announced that they have successfully combined two time crystals. A breakthrough opening new avenues for the development of quantum computers.
Harnessing quantum mechanics to make the impossible possible
The possibility of building a perpetual motion machine, continuing to operate without external energy input, is a famous scientific hypothesis. In order to make the impossible possible, researchers are turning to the strange world of quantum mechanics, the laws governing the infinitely small.
A strange phase of matter, time crystals were originally theorized in 2012 by the Nobel laureate Frank Wilczek. Obtained for the first time in the laboratory in 2016, these have recently been able to be created at room temperature.
While the atoms composing their ordinary counterparts (such as quartz or diamond) are organized as a fixed three-dimensional grid, with crystal patterns repeating only in space, the state of these particles oscillates periodically in time crystals, whose structure therefore repeats itself both in space and time. This results in perpetual motion.
As part of the work detailed in the journal NatureCommunicationsBritish, Russian and Finnish researchers have succeeded in coupling for the first time two temporal crystals made up of quasi-particles called ” magnons », forming a single macroscopic system with two levels.
A two-level macroscopic system
Spatially distinct, the two time crystals were created as condensates of Bose-Einstein. These groups of particles essentially behave like a single atom at ultra-low temperatures, making the strange quantum effects visible on the macro scale.
In this case, the researchers cooled helium-3 (a rare isotope of helium that is missing a neutron) to -273.15°C, or one ten-thousandth of a degree above absolute zero. . At this temperature, helium-3 creates a superfluid, that is to say a liquid whose viscosity is zero. The two crystals were then brought together so they could interact.
With a two-tier system forming the building block of a quantum computer, the study’s authors believe the new work opens up the possibility of using these strange crystals as quantum bits, or qubits.