UO physicist Tien-Tien Yu receives New Horizons prize

Theoretical physicist Tien-Tien Yu has received the New Horizons in Physics award for her collaborative work with an international research team and their contributions to the field of “light dark matter.”

Part of the prestigious Breakthrough Prizes, Yu’s New Horizons award is one of six accolades handed out for early-career achievement in physics and math. She will split a $100,000 prize with her three collaborators, Rouven Essig, an associate professor of physics at Stony Brook University; Javier Tiffenberg, an associate scientist at Fermilab; and Tomer Volansky, an associate professor at Tel Aviv University.

"Given the amount of time and effort that has gone into this work, it's nice to receive this level of recognition,” Yu said. “However, it is also very humbling to receive such an award as there are many other qualified people who are equally deserving."

The New Horizons prize recognizes early career scientists who have already made a substantial impact on their fields. Yu and her colleagues have pioneered a new approach in the search for dark matter, the mysterious substance that accounts for about 80 percent of all matter in the universe. Specifically, the team has led the way in the hunt for a class of low-mass dark matter known as light dark matter through the experiment known as SENSEI.

“SENSEI is the first dedicated experiment looking for dark matter in this region,” Yu said. “I’m trained as a particle physicist, but we had to learn some condensed matter theory in order to do the calculations that we needed to figure out what the signature would look like in these things.”

Prior to joining the UO in 2018, Yu served a fellow in the theoretical physics group at the CERN particle physics laboratory in Geneva, Switzerland, and as a postdoctoral associate at the Yang Institute for Theoretical Physics at Stony Brook University with Essig. Starting in 2014, the team began theoretical work involving sub-GeV dark matter, or dark matter with mass less than that of a proton. In 2017, they began the SENSI experiment.

The research represented a departure from scientific efforts focused on a larger class of dark matter known as weakly interacting massive particles, or WIMPs. By making slight modifications to existing technologies, Yu and her team realized they could alter the potential of experiments to look for light dark matter. They employed sensors called skipper CCDs — short for charge coupled devices, which are found in digital cameras and were already in use by physicists in search of WIMPs — and the Sub-Electron Noise Skipper-CCD Experimental Instrument, or SENSEI, was born.

“Light dark matter has become kind of a hot topic over the last few years,” Yu said. “The field has really taken off.”

While Yu, Essig and Volansky have been focused on the theoretical side of the scientific problem, Tiffenberg and his Fermilab colleague Juan Estrada have been the lead experimentalists. The detection equipment is physically housed at the Department of Energy’s Fermilab, but the team is developing new detectors for a full-scale experiment to be run at the Canadian SNOLAB laboratory deep underground. 

Although there may be potential uses for the research in neutrino physics, nuclear reactor monitoring and quantum imaging, the research is largely fundamental, meaning researchers are driven primarily by a curiosity for answers. The research is funded by the Heising-Simons Foundation and Fermilab through the Department of Energy. 

Physics professor Richard Taylor said the award represents a point of pride for the UO’s Department of Physics, which he heads. 

"In addition to the prestige of the award, this is very exciting news because this award is often a signature of work that will lead to major breakthroughs in the future,” Taylor said. “In her short time here, not only has Tien-Tien excelled at her research, but she is an excellent teacher and has contributed in many ways to our mission.”

Yu says she will donate her share of her winnings to a cause she cares about. She plans to attend an awards ceremony in March for the prize.

Known as the “Oscars of science,” the Breakthrough Prizes are a relatively new cluster of awards funded by top Silicon Valley executives including Facebook’s Mark Zuckerberg and Google co-founder Sergey Brin. Known for their prestige and high-dollar prizes, the Breakthrough Foundation has awarded more than $250 million to almost 3,000 scientists since its founding in 2012.

UO mathematician Ben Elias received a New Horizons prize in mathematics in 2017.

By Lewis Taylor, University Communications