1. Doping-induced Quantum Critical Point in Sc3.1InEmilia Morosan, William Marsh Rice University, DMR 0847681 Quantum criticality and the attendant novel phenomena (non-Fermi liquid behavior, unconventional superconductivity etc) have been extensively studied in heavy fermions (HFs). However, analogous studies in itinerant ferromagnets (IFMs) are difficult, despite the less complex electron properties in the former compounds. A quantum critical point (QCP) has been reached for the first time in the IFM Sc3In by doping. Very small dopant amounts destabilize the weak ferromagnetic ground state, and drive the system through the quantum phase transition in a non-mean-field manner. The critical scaling at the QCP indicates that (i) quantum spin fluctuations are responsible for the T = 0 transition and that (ii) there are significant similarities between this system and the HF superconductor URu2Si2, and just as important differences between Sc3In and ZrZn2, the only two known IFMs with no magnetic elements. Fig. 1. (Sc1-xLux)3.1In: (a) Examples of Arrott-Noakes isotherms M1/ vs. (H/M)1/ with a linear fit (solid line) at TC and (b) scaling plots M|t|- vs. H|t|- for x = 0.005; (c) The temperature-dependent ordered magnetic moment M0 (symbols) scales with |t| (solid lines) for x  0.01. Fig. 2. (Sc1-xLux)3.1In: (a) The effective moment  is virtually composition-independent. (b) The T – x phase diagram displays the QCP at xc = 0.03  0.01.

2. Doping-induced Quantum Critical Point in Sc3.1InEmilia Morosan, William Marsh Rice University, DMR 0847681 REU undergraduate students and RET high school teachers spend 10 weeks each summer in the Morosan lab and learn basic research skills. During this past summer, REU student Jose Tusell (LoneStar College) and RET high school teacher Katherine Celestine have worked on single crystal growth and crystallographic characterization of various intermetallic compounds. In their attempt to find novel itinerant ferromagnetic systems, the interns learned the basics of crystal structures and magnetism, as well as materials synthesis. The teacher built a balls-and-sticks model of the crystal structure for one of the compounds she worked on, to be included in the curriculum for advanced physics and chemistry high school students as part of a new component on crystallography, crystal symmetry and xray diffraction.