This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: According to quantum electrodynamics, the theory describing interactions between light and electrically charged particles, a sufficiently strong electric field can, in principle, convert some of its energy into particles and their antimatter partners. A particle's antimatter partner has the same mass and, for electrically charged particles, the opposite electric charge.
The creation of particle–antiparticle pairs via an electric field and from the vacuum is known as the Schwinger effect. As the production of these pairs is strongly suppressed at electric field strengths that can be realized in a laboratory setting, observing this effect experimentally has so far proved challenging. Researchers at the University of Science and Technology of China and other institutions have now introduced an experiment that could be used to simulate and study this rare particle production process.
Their experiment, outlined in a paper published in Physical Review Letters, entails representing particles and electric fields through the arrangement and motion of ultracold rubidium atoms trapped in an optical lattice, a laser light-based pattern that can trap atoms. "We were inspired by the Schwinger effect, the prediction that a strong electric field can spontaneously create electron-positron pairs from the vacuum," Zhen-Sheng Yuan, co-senior author of the paper, told Phys.org. "This is an example of 'false vacuum decay,' and in its original form it has never been observed directly.
Our goal was to build a simple, controllable laboratory model with cold atoms, where we could simulate this process and tune how it unfolds." In their experiments, Yuan and his colleagues used laser light to trap ultracold rubidium atoms in a one-dimensional chain, a straight row of tiny optical traps. Every second trap on this chain contained two atoms, while the traps in between were empty. "This arrangement is a 'false vacuum,' a state that can release energy by creating particle-antiparticle pairs," explained Yuan.
"We then changed the settings so atoms could hop between neighboring sites in a way that mimics pair creation, tuning the background electric field to control the process. A quantum gas microscope imaged the atoms at different times, letting us watch it happen." The researchers changed the mass of the simulated particles in their system and the background electric field to determine how these changes affected the production of particle-antiparticle pairs. They found that when the simulated particles were heavier or when the electric field became too dominant relative to other interactions in their model, fewer pairs formed.
"We also linked pair production directly to the 'vacuum persistence amplitude'—whose squared magnitude gives the probability that the initial vacuum survives—and saw long-lived oscillations in some physical limit," said Yuan. "Together, these show how cold atoms bring otherwise hard-to-observe quantum-field processes into a controlled laboratory." Discover the latest in science, tech, and space with over 100,000 subscribers who rely on Phys.org for daily insights. d research that matter—daily or weekly. This study introduces a new experimental platform for simulating and studying the production of particle-antiparticle pairs.
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