Abstract

We report the experimental results of temperature dependent polarized As K-edge extended x-ray absorption fine structure (EXAFS) of LaFe1-xCoxAsO (x=0.0 and 0.11) single-crystals. By aligning the Fe-As bond direction in the direction of the x-ray beam polarization we have been able to identify an anomaly in the Fe-As bond correlations at the tetragonal to orthorhombic transition at 150K, while previous investigations with standard unpolarized EXAFS of undoped LaFeAsO powder samples were not able to detect any such anomaly. Using our approach we have been able to identify in the superconducting doped sample, LaFe0.89Co0.11AsO, a broad anomaly around 60 K. The low temperature anomaly has good correlations with the temperature dependence of several properties like resistivity, magnetic susceptibility, linear thermal expansion, etc indicating the emergence of the dynamical oscillations of the Fe - As pairs

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.