Physics Illinois doctoral student Yu Gan has been selected to receive the Lam Research Corporation’s Outstanding Graduate Student Award for his work in developing innovative inelastic x-ray scattering techniques, which have implications for our understanding of the fundamental behavior of electrons in novel materials.
Gan works in experimental condensed matter physics as part of Professor Peter Abbamonte’s group. Gan’s thesis work employs inelastic X-ray scattering to precisely measure the electronic properties of materials, with an emphasis on imaging the ultrafast response of materials to perturbations. In an invited article in a special issue of Chemical Physics on attosecond phenomena (v. 414, pp 160-167), Gan describes his new experimental technique using coherent inelastic X-ray scattering.
The new technique is based on one Abbamonte had developed that can produce “movies” of ultrafast electronic behavior of materials. Abbamonte’s technique assumes a homogeneous system of electrons, a reasonable first approximation for many materials. Gan’s technique does the same for materials with an inhomogeneous distribution of electrons, theoretically recovering the material’s complex electronic behavior for imaging.
“I’m trying to refine the technique to make it applicable to more materials,” explains Gan. “We may be able to use it to process data to get real-time and -space data out. Ultimately, I am imaging what electrons do in a system as a result of perturbations, like when we remove or add an electron. This response to perturbation is a fundamental property of a material.”
"Gan has done an outstanding job of giving life to this experimental concept,” Abbamonte comments. “The study would not have been possible without his fearlessness and attention to detail.”
Gan has also been using inelastic X-ray scattering to study graphene, an inhomogeneous material with many exotic properties. His recently completed experiments at Argonne National Laboratory look in particular at graphene’s electronic interactions, measuring whether these are as strongly correlated as theoretically postulated.
Gan chose this field of research for his graduate studies because he wanted the opportunity to build an experiment from the ground up. As an undergraduate, he did research in high energy physics using data from Fermilab:
“When you are part of a collaboration with 3,000 physicists, working on one small piece, it’s easy to feel your contribution is insignificant. I wanted more of a table-top research experience from my graduate work,” remarks Gan. “X-ray groups are smaller, but still have features of big science. I have the best of both worlds—I get to work with staff scientists at world-class, state-of-the-art facilities, but also get to design and execute my own experiment.”
Gan has been a visiting scholar at Argonne National Laboratory since 2011, working under staff scientist Diego Casa. Gan has co-authored a number of publications in peer-reviewed journals and presented his findings at many conferences across the US during his tenure at Physics Illinois.
Gan said working under Abbamonte has been a great benefit to him: “Peter is a great guy. He’s very enthusiastic about science.”
Gan was a National Merit Scholar (2003). He received his bachelor’s degree in physics from Princeton University (2007) where he completed an undergraduate thesis entitled, “An Investigation of LEP's Sensitivity to the NMSSM Higgs Sector,” with advisor Christopher Tully. He also completed a minor in theater and dance.
The Lam Research Corporation Outstanding Graduate Student Award is made possible by a generous gift from the Lam Research Corporation of Fremont, CA.