Spotlight on new faculty: Chen-Yu Liu

10/27/2022 4:03:39 PM

Siv Schwink for Illinois Physics

The Department of Physics at Illinois has welcomed an extraordinary set of six new faculty members since 2020. We will feature each of them here over the next few weeks. Check back regularly to learn more about the exciting work these new faculty members are doing.

Illinois Physics Professor Chen-Yu Liu

Chen-Yu Liu is a nuclear physicist working to answer some of the most challenging open questions about the neutron, a subatomic particle present in all atomic nuclei except those of ordinary hydrogen. Liu’s neutron research sheds light on the creation of matter and nucleosynthesis in the early universe. It also has implications for our understanding of physics beyond the standard model.

Made up of quarks and subject to the so-called strong force, the neutron is about the same mass as a proton, but has no electric charge. The fundamental properties of the neutron have been extensively studied, but certain measurements continue to present tremendous experimental challenges. Liu develops novel experimental techniques to elucidate the neutron beta-decay lifetime, neutron decay asymmetries, and the electric dipole moment of the neutron. Much of Liu’s work involves ultra-cold neutrons, which have low kinetic energies and so can be stored in material bottles or magnetic traps for up to a few minutes at a time—long enough to enable higher precision measurements.

Liu is currently leading three collaborative experimental efforts at national facilities. The Ultra Cold Neutron Half-Life experiment (UCNτ) at Los Alamos National Lab (LANL) and the Beam Neutron Lifetime 3 experiment (BL3) at NIST measure the neutron lifetime through disparate experimental approaches. The Neutron Electric Dipole Moment experiment (nEDM) at LANL measures the electric dipole moment (EDM) of the neutron using nuclear magnetic resonance (NMR).

Liu joined the faculty at Illinois Physics in August 2022 as a full professor.

“I look forward to working with the excellent, highly motivated graduate students and undergraduate students in my research lab,” says Liu. “I have four research projects on fundamental neutron physics and precision measurement of beta-decays. Among these activities, I am very excited to start building a new proton detection scheme to tackle the outstanding puzzle on the neutron lifetime. My research group was just awarded a NIST Precision Measurement Grant to start this work.”

Read more about the experiments Liu’s group is collaborating on here.