Wednesday, 20 March 2019: PhD Thesis Defense by Alexander Stangl
The PhD Researcher Alexander Stangl from the Superconducting Materials and Large Scale Nanostructures (SUMAN) Group at ICMAB will defend his PhD thesis on Wednesday, 20 March 2019, at 11 am at ICMAB-CSIC.
Oxygen kinetics and charge doping for high critical current YBCO films
by Alexander Stangl, Superconducting Materials and Large Scale Nanostructures (SUMAN) Group, ICMAB
Date: Wednesday, 20 March 2019 Time: 11 am Venue: Sala d'actes Carles Miravitlles, ICMAB-CSIC
Abstract: Superconductivity in YBCO is governed by hole doping into the CuO2-planes via the oxidation of the crystal. This so-called oxygenation process is the main subject of this thesis. A high oxygen content in YBCO is a prerequisite for its exceptional superconducting properties, such as the highest achievable critical current densities.
In this work we have obtained a fundamental understanding of the oxygen incorporation mechanisms into the structure and have identified the rate determining step. Additionally we have demonstrated the influence of heat treatments on the microstructure and the chemical composition of the surface. The thorough understanding of the oxygenation process enabled us to reach the overdoped state of YBCO and to increase the critical current to record high 90MA/cm² at 5K, a third of the depairing current density.
Supervisors:
Prof. Teresa Puig, Superconducting Materials and Large Scale Nanostructures, ICMAB
Dra. Anna Palau, Superconducting Materials and Large Scale Nanostructures, ICMAB
PhD Committee:
President: Prof. John Kilner, Imperial College, London, United Kingdom
Secretary: Prof. Albert Tarancón, IREC, Barcelona, Spain
Vocal: Prof. Jacobo Santamaria, Universidad Complutense de Madrid, Spain
