Colloquium

STM Studies of Cuprates and Pnictides

Dr. Vidya Madhavan
Boston College
Department of Physics
Wednesday, September 23, 2009
Higgins 310, 4 pm

Over the last two decades, Scanning Tunneling Microscopy has emerged as a powerful tool for the study of correlated electron systems. The fascinating high temperature superconductors fall into this category, where STM studies have been critical in furthering our understanding of these materials at the nanoscale. In this talk I will explore two distinct high temperature superconductors: electron doped cuprates and the parent compounds of the newly discovered pnictides. The first part of the talk will focus on the yet to be settled question of the paring mechanism in the cuprates. Our STM data shows that in addition to phonons, magnetic excitations couple strongly to the electrons in this system. I will discuss of the ramifications of our observations. In the later part I will focus on our recent contributions to understanding the surface of the parent pnictide SrFe2As2.