Meet Xiaoqian Chen, NSLS-II Beamline Scientist

Xiao leads the quantum materials program at NSLS-II’s Coherent Hard X-Ray Scattering beamline

You’ve already spent a few years at Brookhaven, starting in 2016. What brought you back to the Laboratory?

My history with the Laboratory goes back to when I was a user at the original National Synchrotron Light Source (NSLS). I was in graduate school, and my group had our own beamline at NSLS, X1B. I was the person maintaining that beamline, so I came to know many people here.

When I became a postdoc, I decided to join the x-ray scattering group in Brookhaven’s Condensed Matter Physics & Materials Science Department because we shared the same research interests and coherent x-ray science was emerging. I joined when the Coherent Soft X-ray Scattering (CSX) beamline at NSLS-II had just achieved first light. I was able to participate in the first experiments there, and that was my postdoc work.

I then took a postdoc position at DOE’s Lawrence Berkeley National Laboratory and worked more on coherent x-ray science. After three years, I was offered a position at CHX to lead the quantum materials program.

What does your role at CHX entail? What kind of research do you do?

My research, in a broad sense, is in the field of condensed matter physics, looking at quantum materials. These are materials that have behaviors that are very heavily guided by quantum mechanical effects. For example, some have superconducting properties, and some have interesting magnetism. With help from my postdoc, I am looking into discovering new quantum effects in materials, and our work is supported by a Laboratory Directed Research and Development (LDRD) grant. Apart from my own research, I prepare an environment at CHX for scientists in our community to perform coherent x-ray experiments and study dynamical properties in their materials.

At CHX, we use coherent x-ray photons to track the dynamics inside materials. We can detect electron dynamics as fast as the nanosecond time scale with our recent detector installation. I’m currently trying to detect and study dynamics in materials that take place at that time scale. The ultimate goal is to find a signature of quantum entanglement. This property is a specific type of interaction between electrons; they show very different behavior from electrons in classical materials.

There are some other new capabilities that we are excited for users to experience. We have added a resonance scattering capability to look at element-specific information. For example, we can look at electrons in specific orbitals. We also added low temperature capability with a new cryostat that can chill samples to 4K. That’s very cold, and it will be very useful for studying quantum materials.

Read more on the NSLS-II website

Image: Xiaoqian Chen is a physicist and beamline scientist with the complex scattering program at the National Synchrotron Light Source II (NSLS-II), a U.S. Department of Energy (DOE) Office of Science User Facility at DOE’s Brookhaven National Laboratory. At NSLS-II’s Coherent Hard X-ray Scattering (CHX) beamline, she studies materials with quantum behaviors and guides users in their investigations into quantum materials.