Experimental trapped-ion setup used to generate the family of squeezed states. The ion is confined between electrode structures and controlled using precisely tuned laser fields. Credit: David Nadlinger.

Researchers at the University of Oxford have demonstrated a new type of quantum interaction using a single trapped ion. By creating and controlling increasingly complex forms of "squeezing" – including a fourth-order effect known as quadsqueezing – the team has, for the first time, made previously unreachable quantum effects experimentally accessible.

The approach also provides a new way to engineer these interactions, with potential applications in quantum simulation, sensing, and computing. Their results have been published in Nature Physics .

Many systems in physics behave like tiny objects that vibrate or swing back and forth, like a spring or a pendulum. In quantum physics, these are known as quantum harmonic oscillators.…