Evolution of nanoscale charge order in superconducting YBCO nanostructures

Research Project, 2017 – 2020

The discovery of charge density waves (CDW) in the cuprate high critical temperature superconductor (HTS) families, both hole and electron doped, has reinforced the idea that some of the secrets of the unconventional properties of this class of materials are hold in their mesoscale properties. Within this project I will investigate by resonant x-ray scattering YBa2Cu3O7-δ (YBCO) nanostructures with cross sections down to 50×30nm2, with superconducting properties close to the as-grown films. I will determine the evolution of the charge order with the dimensionality of the system and in magnetic field, to understand its interplay with superconductivity at the nanoscale. For the next three years I will bring my expertise in oxide thin film growth and nanopatterning of HTS, acquired at Chalmers to the group, at the Politecnico di Milano, with a recognized leadership in the field of x-ray spectroscopy and strongly correlated electron systems. Under their guidance, and with the theoretical support of the Devereaux group (Stanford), I will perform resonant x-ray scattering experiments on YBCO nanostructures mainly at the ESRF (the European Synchrotron in Grenoble), at the European XFEL (in Hamburg) and at the LCLS (the Coherent Light Source in Stanford). The outcome of my experiments could help to elucidate the connection between the CDW order and the superconducting phenomenon, possibly leading to a better understanding of the microscopic mechanisms responsible for HTS.