Graduate Students
Will Clay
I am a graduate student in Physics and I joined the Shen group in the summer of 2006. I am currently working on a project to research and develop Diamondoids, which are molecular crystals of diamond-like hydrocarbons. Little is known about the properties of the larger Diamondoids, so we are currently pursuing many different avenues of research on them. Possible applications include superconductivity, nano-scale devices, and field emission electronics. I find this project interesting because it enables me to do work in a broad range of disciplines including chemistry, material science, and electronics, while still being able to do pure physics research.
Ruihua He
I graduated from Fudan University in Shanghai, China and am now in my third year of Ph.D. candidacy. My research interest currently focuses on charge (spin) density wave (CDW/SDW) ordering in complex materials, which include (Nd-doped) La2-xSrxCuO4 high-temperature superconductor and R2Te5 rare earth telluride. Besides the major technique, ARPES, I am using (at SSRL/ALS/McCullough HeLM), I am developing an in-situ technique for the characterization of superconducting transition temperature of sample surfaces, which will serve my long-term interest in stepping into a largely unexplored area, the surface superconductivity.
Hitoshi Ishiwata
I am a first year PhD student in the Electrical Engineering department. I joined the Shen group in autumn 2008. I received a BS and MS from Waseda University in Japan. I am working on growth and electrical application of diamond. Diamond's hardness and sparkle make it popular as jewelry, but it also has a huge potential for electrical application such as room-temperature superconductivity, quantum computing, next generation solar cell (PETE project), spintronics and wide bandgap power devices. Its exceptional properties such as superconductivity and negative electron affinity is not yet fully understood. My goal as graduate student is to reveal those mechanisms by developing growth techniques and studying electrical applications. Diamond is also available in the nano form--diamondoids--so the properties of diamond can be studied in detail from micro scale down to nano scale for exciting unexplored physics.
Worasom Fern Kundhikanjana
I am a graduate student in the Applied Physics Department. I join the Shen group in summer 2007. I received a BS from Brown University. I am working on developing a Near Field Microwave Microscope. This technique probes the electrical properties of a material, i.e. the dielectric constant and conductivity. Our primary goals are improving the sensitivity of the technique and looking for possible applications such as studying ferro electric material, nano particles in biological system, and system with a first order phase transition near room temperature.
Zhongkai Liu
I am currently a graduate student in physics department and I received my BS degree in Tsinghua University, China. Now I'm working on developing the new time- and spin- resolved photoemission spectrometer. With the capability of detecting electron spins, I'm looking forward to study novel systems such as magnetic material and spin-orbit coupling system. And also, with the time resolution, we will be able to study system's dynamical behavior, which would lead us to some really interesting physics problems.
Dan Riley
I received my BSE in engineering physics from Case Western Reserve University in 2008. I am currently a PhD student in the Physics department, and I joined the Shen group in 2008. I work on the Photon Enhanced Thermionic Emission (PETE) project, which is a scheme to increase the energy conversion efficiency of thermionic devices to be implemented as topping cycles for solar thermal systems. A PETE device combines the photoelectric effect and thermionic emission in a synergistic fashion. A solar thermal system in tandem with a PETE device has potential to be groundbreaking, efficient and economically viable solar energy conversion system. I greatly enjoy the diversity of expertise that the development of such a device requires. I have a strong interest in the wide scale implementation of renewable energy sources, from their initial scientific development to the creation of a device that is economically and environmentally beneficial. My goal as a graduate student is to advance our knowledge in solar energy conversion to benefit mankind.
Felix Schmitt
I received a Diplom from the Julius-Maximilians-Universitt Wrzburg in Germany in 2006. I was doing PES on the Kondo system CeSi2 then. I have always been fascinated with solid state physics and how systems with a vast amount of particles and countless interactions and correlations sometimes organize themselves to such a high degree that description and understanding is actually possible, and so I continue by pursuing a PhD degree in Stanford in a very similar area: Complementary to the p-doped cuprate high transition temperature superconductors --- as studied by my fellow team mates ---, the e-doped ones have a very similar doping-temperature phase diagram. I am fascinated by the question of how much of the underlying physics of those two is the same. ARPES for me is the most direct and elegant probe to learn more about these e-doped cuprates, like NCCO, PCCO, etc.
Jared Schwede
I am a graduate student in the department of physics, and I began work in the Shen lab in 2008. I am interested in photoexcitation with an eye towards energy applications. The Shen group is intimately familiar with the processes of photoexcitation and photoemission. My hope is to apply this enormous expertise to gain unique insight into novel solar energy designs.
Jonathan Sobota
I graduated from Cornell University
in 2007 with a BS in Engineering Physics. I'm now a
graduate student in the Department of Physics. I'm
fascinated by the way in which the countless constituents
of matter, and the interactions between them, conspire
to give a material its macroscopic properties-- not
only properties that we're familiar with, but also
exotic and counterintuitive properties. My goals for
future work include:
1) to use photoemission to study magnetic materials and
the high-temperature superconductors; and
2) to help advance the technology used to probe these
materials. Currently, I'm contributing to the development
of our time- and spin- resolved spectrometer
Inna Vishik
I am a graduate student in the Applied Physics department, and I joined the Shen lab in 2007. My interests lie in strongly-correlated transition metal oxides, and in particular, the cuprate high-temperature superconductors. Whereas BCS superconductivity emerges from a well understood Fermi-liquid normal state, the "normal" state of high temperature superconductors--the pseudogap --is still unexplained. To that end, I am using Angle Resolved Photoemission Spectroscopy to study the pseudogap of Bi-2212. As the resolution of ARPES has improved in recent years, we are able to get a detailed picture of the phase diagram above Tc as a function of doping. From this, progress can be made towards understanding the origin of the pseudogap and its relation to superconductivity.
Ming Yi
I am a graduate student in the physics department. I joined the Shen group in the spring of 2008. When I was an undergraduate at MIT, I studied the high Tc cuprate BSCO using STM, and have since been very fascinated by the high level of ordering in strongly correlated systems and the wide range of unusual and exotic properties that arise. I am now using ARPES to probe and study electron dynamics and ordering phenomena in rich systems such as the newly discovered iron pnictide superconductors, and to contribute to piecing together the larger picture that is fundamental to all these correlated systems.
