Four-Year College Faculty-Student Team Fellowships Program
Prof. Arlene Ford and student Jacob Johnson
Simpson College, Indianola, Iowa
worked with Shireen Adenwalla, Physics.
Dr. Arlene Ford and student Jacob Johnson working in Dr. Shireen Adenwalla´s lab, look at resonance peaks from inter-digital transducers (IDT´s) made of platinum on Y-cut Lithium Niobate substrates. These resonance peaks are used to characterize the IDT devices before they can be used in surface acoustical wave applications such as switching the magnetization direction of lithographically patterned ellipses made of cobalt. The shape anisotropy will be observed from the magnetization loops measured using the magneto-optical Kerr effect (MOKE). Jacob was also able to design a custom electromagnet as well as to fabricate (machine) pieces of the magnet, assemble its components, as well as test and calibrated the completed magnet. In addition to the fabrication and characterization of the IDT's and the calibration measurements of the custom electromagnet, MOKE (Magneto Optical Kerr Effect) measurements were also performed on both Co/Pt and Co/Pd thin films deposited on piezoelectric substrates to investigate their interlayer behavior.
Prof. Yung Huh and student Eric Krage
South Dakota State University, Brookings, SD
worked with David Sellmyer, Physics.
"Eric Krage, undergraduate physics major, and Professor Yung Huh from South Dakota State University are working on magnetic and structural properties of (1) the melt-spun ribbons of MnxGa, where x varies from 1.0 to 3.0, and (2) the LaCo5-xFex systems. Mn atoms in the MnxGa, are then replaced by either boron or carbon atoms to enhance the magnetic properties for commercial applications. Thin films are also prepared and investigated by magnetron sputtering system, e-beam, and pulsed laser deposition (PLD) systems. Highly textured thin films of LaCo5 (hard) and La2Co17(soft) phases are obtained using the PLD system. This process takes advantage of the coupling of the hard and soft phase magnets to increase the magnetocrystalline anisotropy. Works also include the growth and characterization of rare-earth based permanent magnet LaCo5-xFex (x = 0, 0.25, 0.5, 0.75). The systematic study of Fe doping effect was conducted using SQUID and VSM magnetometers, XRD, SEM, TEM, and EDX."
Prof. Luis Rosa and students Eduardo Vega (left), Gerson Diaz (second right), and Fernand Torres (right)
second from left: Physics REU student John Paul Cordova
University of Puerto Rico - Humacao
worked with Peter Dowben, Physics.
Band Structure Analysis on TCNE and TCNQ functionalized p-benzoquinonemonoimine zwitterions
"We are interested in analyzing the TCNE and TCNQ functionalized p-benzoquinonemonoimine zwitterions because they can be paired with graphene to produce a useful chemical specific sensors and gated graphene devices.
We modeled our functionalized zwitterions using semi-empirical calculations to find the HOMO-LUMO gap at different distances between the dipoles and different relative angles between them.
We secured samples of TCNE, TCNQ, and a methoxy benzyl functionalized zwitterions and measure the HOMO-LUMO gap on all samples to compare."
Prof. Mark Plano Clark and student Brett Amen
Doane College, Crete, NE
worked with Axel Enders, Physics.
"Our project has been to develop a low cost scanning tunneling microscope that could be used in high school and college physics labs. This summer we spent our time working on both our STM and our tip etching station. One major obstacle yet to overcome is consistent coarse motion of the STM head that will allow controlled approach to a surface to be studied. We have changed our coarse motion motor from a "slip-stick" motion to a "walker" motion where four linear piezo actuators move independently under microcontroller control. Programming of the microcontroller is complete and testing of coarse motion is currently underway. We have also measured the x-y scan motion dimensions by placing the scanner in one leg of an interferometer. The total x-y scan range is 2.2 x 2.2 microns. Another aspect of our work this summer has involved experimenting using carbon fiber tips instead of PtIr wire tips. Carbon fiber tips are cheaper and, we hope, more robust than PtIr. We plan to begin testing the carbon fiber tips under actual scanning conditions and that we will have a fully functional STM available to students by the end of the project."