One tiny particle could complicate predictions of physics theorists

Picture an 11,000-pound elephant standing on a bathroom scale. Now imagine that scale is so precise, it can tell that you placed a couple of sunflower seeds on the elephant’s back.

That is the level of precision achieved by an international collaboration, including Cornell researchers, hosted by the U.S. Department of Energy’s Fermi National Accelerator Laboratory. The group set out to measure the magnetic anomaly of the muon – a tiny, elusive particle that could have very big implications for understanding the subatomic world.

On June 3, the collaboration – which consists of 176 scientists from 34 institutions in seven countries – announced that the third and final round of data, collected between 2021 and 2023, has been analyzed, and the researchers have increased the precision of their measurement by more than a factor of four, to 127 parts-per-billion.

Read the full story in the Cornell Chronicle.

New technique turns ‘noisy’ lasers into quantum light

Scientists have discovered a way to convert fluctuating lasers into remarkably stable beams that defy classical physics, opening new doors for photonic technologies that rely on both high power and high precision.

Lasers are essential tools in science, industry and medicine, but increasing their power often results in “noise” – unpredictable fluctuations in intensity that disrupt applications requiring consistent, stable light.

Researchers led by Cornell and the Massachusetts Institute of Technology have demonstrated how noisy, amplified lasers can be transformed into ultra-stable beams through a clever use of optical fibers and filters. The technique was detailed May 14 in Nature Photonics.

“What was super surprising is that the noise is so low that there’s no classical laser beam that has those same properties,” said Nicholas Rivera, assistant professor of applied and engineering physics at Cornell Engineering.

Read the full story in the Cornell Chronicle.

Revealing the superconducting limit of ‘magic’ material

Graphene is a simple material containing only a single layer of carbon atoms, but when two sheets of it are stacked together and offset at a slight angle, this twisted bilayer material produces numerous intriguing effects, notably superconductivity.

Now Cornell researchers are making headway into understanding how the material achieves this state by identifying its highest achievable superconducting temperature – 60 Kelvin. The finding is mathematically exact, a rare feat in the field, and is spurring new insights into the factors that fundamentally control superconductivity.

“Looking ahead, this paves the way for understanding what are the possible degrees of freedom that one should try to control and optimize in order to enhance the tendency towards superconductivity in these two-dimensional material platforms,” said Debanjan Chowdhury, the Joyce A. Yelencsics Rosevear ’65 and Frederick M. Rosevear ’64 Assistant Professor of physics in the College of Arts and Sciences (A&S).

Read the full story in the Cornell Chronicle.