Peter Hirschfeld

Visiting Professor, University of Florida 

Possible pair density wave in BSCCO-2212 from the perspective of STM experiments

STM has the ability to image atomic-scale features on superconducting surfaces. Comparison of such images with theory has sometimes been frustrating, since STM images typically contain much more detail than that predicted by current theoretical calculations for lattice models. I will therefore first discuss the marriage of first-principles electronic structure theory with phenomenological theories of superconductivity to calculate images of high-Tc superconducting surfaces within so-called Bogoliubov-de Gennes-Wannier (BdG-W) theory. This approach can naturally explain a host of longstanding puzzles posed by STM images cuprates. In the second part of the talk, I'll discuss application of the theory to the charge order problem in superconductors, in particular the longstanding observation of "checkerboard" charge order in BSCCO-2212. A calculation of modulated pair density wave states within a t-J model reproduces many aspects of STM experiments on underdoped BSCCO.

Zoom link: https://ucph-ku.zoom.us/j/66020280873