Scientists Watch New Particles “Pop Into Existence” on a Quantum Computer

A new Duke Quantum Center study shows how quantum simulators can help researchers explore particle formation and the conditions that followed the Big Bang.

Quarks are the fundamental building blocks of matter, but they never exist alone. Bound tightly inside protons and neutrons, pairs of quarks behave as if connected by a taut string. Pulling them apart takes so much energy that when the connection finally snaps, that built-up energy transforms into entirely new particles. This process, known as string breaking, normally occurs only in extreme environments such as the Large Hadron Collider or the immediate aftermath of the Big Bang.

A team led by faculty at the Duke Quantum Center has now recreated analogous behavior using a quantum simulator built from 13 trapped ions, or electrically charged atoms. By programming the ions to follow a mathematical model, the researchers could track how a simulated string broke and effective charges emerged. The results, published September 23 in Nature Physics, are among the field’s first quantum simulations of string-breaking dynamics related to particle-antiparticle formation.

String breaking under laser control

Quarks themselves are about a billion times smaller than an atom and cannot currently be observed directly. A quantum simulator makes it possible to investigate a model of their behavior through a system researchers can control. In the Duke experiment, precisely directed laser beams adjusted the interactions among the ions, allowing those interactions to mimic the energy buildup associated with stretching a connection between quarks.