Condensed Matter Seminar

Study of magnetic anisotropy and IEC in GaMnAs-based tri-layer structures by Planar Hall Effect

Jonathan Leiner
(Advisor: Margaret Dobrowolska)

GaMnAs/GaBeAs/GaMnAs trilayer structures were investigated via magneto-transport measurements in hopes of finding evidence of spontaneous antiferromagnetic coupling between the two magnetic layers. Ferromagnetic interlayer exchange coupling between such layers is common, but finding antiferromagnetic coupling has proven much more elusive.

X-ray Absorption Fine Structure Investigation of Uranyl-Phosphate Biomineralization

Xue "Snow" Rui
(Advisor: Bruce Bunker)

A potential remediation method to treat Uranium contamination is to apply dissolved polyphosphate into the contaminated aquifers. The presence of bacteria in systems at high saturation states leads to the nucleation of nanoparticulate uranyl-phosphates within the bacterial cell walls. XAFS spectroscopy was used to characterize the process in both biotic systems and abiotic controls and the structure of precipitate was determined as HUP mineral.

Weak Ferromagnetism in La₂CuMO₆

Matthew Smylie
(Advisor: Howard Blackstead)

There exist a class of materials that simultaneously exhibit magnetic order and superconductivity, and further investigation into these materials may help solve the riddle of HTSC. Investigation of magnetic behavior in the insulating double perovskite La₂CuMO₆ (M=Ru,Ir,Sn) has shown interesting behavior common to other (superconducting) ruthenocuprates, but doping studies have yet to result in clear superconductivity. Recent results of these studies will be discussed.

 

Thursday, October 15, 2009 - 4:00 P.M., NSH 184