The author of the this web page is Eric Reichwein. He is currently an undergraduate physics major at the University of California, Santa Cruz. His interests are mainly in experimental condensed matter physics and physics education. Eric started his career in research in the Proton Computed Tomography group at UC Santa Cruz. After this he began working with Professor Gey-Hong Gweon conducting Angle Resolved Photoemission Spectroscopy (ARPES). ARPES is pronounced ARP-PESS, although Eric frequently pronounces as ARPS. We conduct our experiments at Stanford's Synchrotron Radiation Lightsource (SSRL) beamline V-4. So far Eric has been studying topological bulk insulators (TBI) and is currently writing his undergraduate senior research thesis this bizarre state of matter. Professor Gweon is focusing on extremely correlated electron physics to describe high temperature superconductors. He works in close collaboration with Professor Sriram Shastry. In the summer of 2013 Eric participated in a NSF REU National Nanotechnology Infrastructure Network internship at UC Santa Barbara working in Shuji Nakamura's Group. Shuji Nakamura went on to win the 2014 Nobel Prize in Physics for his work on III-V semiconductors, mainly creating the first blue LED.
I will be helping Dr. Alexei Federov and his post-doc develop a new, state of the art, high resolution spin-ARPES end station at LBNL's Synchrotron. I will probably not be conducting any cutting edge physics research, but I will be figuring out new things related to ultra-high vacuum systems and pumps, hemisphere detectors, electronics, software and mechanical systems. I am really excited about this opportunity and I will keep you updated.
I quote from my researcher advisers (Dr. Gey-Hong Gweon's) webpage: This is a very intersting topic, in many ways. Topological insulator is a new quantum phase of matter, recently proposed theoretically. It is required to be a bulk insulator and a topologically protected surface metal. ARPES data have been crucial in ascertaining the topological insulator nature of various materials, now accepted as topological insulators, even though the bulk crystal of many of these materials has remnant charge carriers and thus is not an insulator. The protected surface state has a strong similarity to the electronic structure of graphene, whose ''Dirac-cone'' electronic structure was measured by ARPES for the first time, in an experiment led by G.H. Gweon.
We are studying these materials from two different perspectives. First, we are studying interaction effects in topological insulators. Second, the surface metallic state in topological insulator materials seems a very good reference to compare with anomalous line shapes in quasi-two-dimensional and quasi-one-dimensional cuprate's that our group study.
We grew LEDs using metal organic chemical vapor deposition (MOCVD) on sapphire and bulk GaN substrates. We then processed these LEDs in the UC Santa Barbara Nanofabrication Facility. The processed starts from activating p-GaN (which Dr. Shuji Nakamura pioneered in the early 90's) then cleaning the samples in a HF bath. After that we use photolithography to lay down the positive and negative electrode contacts and the indium-tin-oxide (ITO) current spreading layer. This process involves using electron beam deposition to lay down smooth layers that are on the nanometer length scale. After that we conducted many temperature dependent tests on the samples. We concluded that there is in fact a dependence on growth plane polarization. These results can be seen in more detail in the Japan Journal of Applied Physics April 2013, Kawaguchi,Nakamura et. al.
Check out the awesome work that the Proton Computed Tomography group is doing at UC Santa Cruz.
I designed a working prototype GUI that would talk to the field programmable gate array (FPGA).