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1. Superconductivity and Quantum Criticality in IntermetallicsDavid P. Young, Louisiana State University & Agricultural and Mechanical College, DMR 1005764 • Our research group has recently been studying the magnetic and transport properties of several binary intermetallic compounds, including: Nb0.18Re0.82, NiBi3, and FeGa3 • Nb0.18Re0.82 is noncentrosymmetric, meaning it lacks a center of inversion symmetry to its crystal structure. While this particular lack of symmetry can lead to unconventional superconductivity (such as in Mo3Al2C), our measurements suggest a conventional classification. • We have synthesized wires and microfibers (see figure) of NiBi3, thus allowing us to accurately measure the material’s critical current density (Jc). Ferromagnetic spin fluctuations, reported for bulk and reduced–dimension samples appear not to influence the critical current. • Ge doping of FeGa3 induces a ferromagnetic metallic state whose physical properties display quantum critical phenomena near a doping level of 5%. (b) (a) Figure (a) Resistivity vs. temperature for a microfiber of NiBi3, showing the superconducting transition near 4.5 K. A scanning electron micro-scope (SEM) image of one of the fibers is shown in the inset picture. 7mm The NiBi3 layer is 80 nm thick, and the core is a solid carbon fiber. The inset graph shows that the critical current density scales as predicted by Ginzburg-Landau theory. Figure (b) SEM cross-section image of a NiBi3 wire. (c) Figure (c) Proposed phase diagram for Ge-doped FeGa3. A ferromagnetic quantum critical point exists at x ~ 0.05.

2. Superconductivity and Quantum Criticality in IntermetallicsDavid P. Young, Louisiana State University & Agricultural and Mechanical College, DMR 1005764 • Our experimental research is integrated into an educational program that enhances student learning in both the laboratory and classroom. • Student training and support within the area of condensed matter physics: Postdocs, graduate students, and undergraduates are trained and gain experience in multiple techniques of materials synthesis and characterization. Furthermore, the general public is exposed to our research through public lectures, demonstrations, and visitations to local middle and high schools. • Student training and support in the life sciences: For more than a decade now we have supported undergraduate research in our lab, providing experience and opportunities for non-physics majors. They are involved in ongoing research projects that often lead to publications. (a) (b) Above. (a) Map showing the universities in Louisiana that participate in the LBRN program which provides research opportunities for life science majors. (b) Large single crystals of FeGa3 synthesized by undergraduate researchers in our lab.