We will have two speakers in honor of Doug Finnemore and Vladimir Kogan

Speaker 1:  David Larbalestier (in honor of Doug Finnemore)

Title: Reflections on the impact of Doug Finnemore on Progressing Superconductivity from Science to Applications and on encouraging a continuing feedback cycle

Speaker 2: John Kirtley (in honor of Vladimir Kogan)

Title: Vladimir Kogan’s 90th birthday celebration

Hosts: Paul Canfield and Sergei Budko

Talk 1 Abstract:  Doug Finnemore has been important to me in my whole scientific career starting from my PhD years at Imperial College 1965-1970. Starting my PhD in 1965 4 years after the Big Bang of high field Nb₃Sn wires, I was given the task of understanding the role of twins generated by the cubic to tetragonal transformation in Nb₃Sn in vortex pinning,  I was bedeviled by first making Nb₃Sn (by arc melting) – and then certifying whether it had or had not transformed.  The huge literature on Type II superconductivity was mostly physics rather than metallurgy.  In my second year I saw a very elegant, clearly written paper on the superconducting properties of high purity niobium describing the properties of high quality Niobium.  That was a lodestone for me that unfortunately I was never able to reproduce in my Nb₃Sn samples. When I came to the United states in 1976 I was involved for about a decade in understanding Nb47wt.%Ti which has become the world's most manufactured superconductor. I used Doug’s paper a lot in this work.  In the 1980’s there was a concern that discovery of new superconductors, especially those with transition temperatures higher than 20 K had languished. Doug was one of the a generation ahead of me who was trying to ensure a solid future for superconductivity and one of these activities was the organization of a workshop in Summer 1983 in Copper Mountain CO to consider the future of superconductivity. He asked Mike Tinkham, Mac Beasley and me to be scientific organizers of that meeting.  There is a funny story about that to be told at this meeting.  Later on, after the discovery of the cuprates, Doug jumped into the enormous Ames and broader DOE effort to understand them.  Trusted by all, Doug was often at the center of organizing meetings that sat at the boundary between science and applications.  I will recall a few of his many vital contributions in my talk. 

Talk 2 Abstract: This talk will concentrate on the component of Vladimir’s work that I know best: his contributions to the study of superconductivity using scanning Superconducting Quantum Interference Device (SQUID) microscopy. After a short introduction to the basics of the Josephson effect and SQUIDs, I will turn to a series of applications of scanning SQUID microscopy to which Vladimir has made central contributions. These applications include experimental tests of the interlayer tunneling model of superconductivity in the cuprate high temperature superconductors, tests of pairing symmetry in the cuprates using the half-integer flux quantum effect, magnetic screening response of superconductors with line and point defects, and the static and dynamic behavior of vortices in thin film superconductors.