top - eletrical resistivity vs temperature bottom - Pressure-temperature phase diagram

1. Pressure-induced superconductivity in CaFe2As2Milton S. Torikachvili, San Diego State University, DMR 0306165 The new compound CaFe2As2 is quite remarkable. As it is cooled down from ambient temperature, it experiences a structural modification near 170 K. However, this structural change is suppressed when the sample is placed under hydrostatic pressures of about 2-3 katm, and superconductivity appears near 12 K. A further increase of pressure brings about another phase transformation, which is detrimental to superconductivity, therefore confining superconductivity to a narrow “dome” between 2 and 9 katm. An understanding of the interactions leading to the suppression of superconductivity at high pressures may lead to a better understanding of the physics in high temperature superconductors. Physical Review Letters101, 057006 (2008) top - eletrical resistivity vs temperature bottom - Pressure-temperature phase diagram

2. Pressure-induced superconductivity in CaFe2As2Milton S. Torikachvili, San Diego State University, DMR 0306165 Education Funding for this awards facilitated the engagement of several graduate and undergraduate students in cutting edge research. Outreach The PI and students developed a set of demonstrations based on the cooling properties of liquid nitrogen, entitled The Cool World of Cryogenics. We take this exhibit to high schools and campus open-houses. Pictures of our last visit to Vista High School (April 2008) are posted on http://picasaweb.google.com/milt2010/VistaHighApril112008?authkey=XnGZFAwrlyw Students from Vista High experimenting with cooling helium-filled and air-filled balloons, and mingling around a magnetic levitation demonstration