Education and Research: Four undergraduates ( Mahnaz Milani-Baladi, Johnny Lin, Sumesh

1. Twin and Defect Engineering for Strong c-axis Flux Pinning in Superconducting YBCOSiu-Wai Chan, Columbia University, DMR-0214650 Twin boundaries, being strong magnetic-flux pinning centers, are engineered to appear in high density. To begin, the boundary energy is measured showing a decrease with increasing processing temperature. This knowledge is exploited to refine twins by increasing annealing temperature with a concomitant increase of the critical current density, and the pinning force. Twin spacing reduces to one fourth as the annealing temperature increases to 680oC with a pinning-force increases by 150% to 3.4 x 108 N/m3 at 77K & 1T. With scientists at ONRL, we generate beneficial extended defects in coated conductor tapes by first decorating substrates with nano-ceria. Important for applications, improved Jc in YBCO with magnetic field along c-axis is observed,.

2. Education and Outreach from DMR Project on SuperconductivitySiu-Wai Chan, Columbia University, DMR-0214650 Education and Research: Four undergraduates (Mahnaz Milani-Baladi, Johnny Lin, Sumesh Bhaskaran, & Hoda Mirafzal ), four graduate students (O. Jongprateep, Josh Hao-Yung Chao, L. Mei & Joan M. Raitano), and one post-doc (Feng Zhang) have contributed. RET:Carla Brauthwaite Summers of 2004 and 2005 Science Teacher at Midwood High School, Brooklyn NYC REU: Christina Diaz , NCSU 2005 Summer. Both Carla and Christina worked on oxide nanoparticles