The bizarre properties of discrete time crystals could be harnessed to detect extremely subtle oscillations of magnetic fields, physicists in the US and Germany have revealed. Publishing their results in Nature Physics, a team led by Ashok Ajoy at the University of California, Berkeley, show for the first time that these exotic materials could have practical uses far beyond their current status as an impractical curiosity.

Discrete time crystals (DTCs) are an exotic phase of matter which break entirely from the rules which apply to classical materials. Whereas an ordinary crystal is made up of atomic or molecular patterns that repeat at regular intervals in space, DTCs have structures that constantly oscillate in repeating cycles when driven by an external protocol, without ever reaching thermal equilibrium.

“Since their initial experimental demonstrations in 2017, there has been enormous excitement surrounding these states,” explains co-author Paul Schindler at the Max Planck Institute of Complex Systems. “Yet a persistent question has remained unanswered: can this exotic order be harnessed for practical applications?”