AVS 59th Annual International Symposium and Exhibition
    Scanning Probe Microscopy Focus Topic Tuesday Sessions
       Session SP+AS+BI+ET+MI+NS-TuA

Paper SP+AS+BI+ET+MI+NS-TuA12
Direct Probe of Interplay between Local Structure and Superconductivity in FeTe0.55Se0.45

Tuesday, October 30, 2012, 5:40 pm, Room 16

Session: Advances in Scanning Probe Imaging
Presenter: M.H. Pan, Oak Ridge National Laboratory
Authors: M.H. Pan, Oak Ridge National Laboratory
W.Z. Lin, Oak Ridge National Laboratory
Q. Li, Oak Ridge National Laboratory
B.C. Sales, Oak Ridge National Laboratory
S. Jesse, Oak Ridge National Laboratory
A.S. Sefat, Oak Ridge National Laboratory
S.V. Kalinin, Oak Ridge National Laboratory
Correspondent: Click to Email
A key challenge in high-temperature superconductivity is to determine the role of local crystallographic structure and chemical effects on the superconducting critical temperature, Tc . Iron chalcogenide superconductors (‘11’) are ideal model systems for deciphering the role of local effects on the superconductivity, primarily because they cleave leaving non-polar surfaces unlike other families of iron arsenide superconductors (‘1111’ or ‘122’) and cuprates . Here, we explore the interplay between local crystallographic structure, composition and local electronic and superconductive properties. Direct structural analysis of scanning tunneling microscopy (STM) data allows local lattice distortions and structural defects across a FeTe0.55Se0.45 surface to be explored on a single unit-cell level. Concurrent superconducting gap (SG) mapping reveals suppression of the SG at well-defined structural defects, identified as a local structural distortion (Guinier-Preston zone). The strong structural distortion is related to the vanishing of the superconducting state. This study provides insight into the origins of superconductivity in iron chalcogenides by providing an example of atomic-level studies of the structure-property relationship.