Michael DeMarco, Professor and Chair in the Department of Physics at Buffalo State College and Research Professor at the University of Buffalo, has been using Mossbauer Spectroscopy since the late 1970's when he was a graduate student at the University of Cincinatti working for S. Jha. For the past fifteen years he has been working on the ruthenates using the 99Ru Mossbauer Effect to study superconducting and magnetic compounds as a function of temperature and external magnetic fields. Recently he has also worked on pnictides and nano-particle systems containing Fe as a function of temperature and magnetic field.
Professor Michael DeMarco, Buffalo State College, Department of Physics, 1300 Elmwood Avenue, Buffalo, NY 14222. Email: Demarcmj@buffalostate.edu. Telephone: 716-878-5004
The Mossbauer Effect forms the basis of this learning experience. It is a nuclear resonance technique from which physics is obtained about the solid state of matter. It involves, specifically, the recoil free fraction, isomer shift, nuclear magnetic splitting and electric quadrupole interaction. These interactions are measured through observation of the Doppler shifted 14.4 keV gamma ray in the decay of 57Co to 57Fe in the source and the resonant absorption in the absorber of interest. This effect can be used as a technique to study any iron bearing compounds from moon rocks to human blood. Presently, for instance, the iron Mossbauer effect is being used to study the iron pnictides which are magnetic and superconducting. And, also, there are some forty or so other Mossbauer isotope probes other than iron such as: Ru, Ir, Os, Au and Sn which can be used in a similar manner.
Specifically in this set of experiments, we will first investigate the standard iron foil experiment using the early seminal paper by S.S. Hanna on the iron Mossbauer effect as a reference. Then we will investigate Hematite, Fe2O3, which was first studied by O.C. Kistner which shows a combined magnetic and electric quadrupole interaction. Participants will expect to learn about gamma ray spectroscopy, some low temperature physics, Mossbauer spectroscopy, radiation safety and magnetism.