19-F NMR Investigation of Iron-pnictide Superconductor LaFeAsO(0.89)F(0.11)

TL;DR

This study uses 19-F NMR to explore the magnetic and superconducting properties of LaFeAsO(0.89)F(0.11), revealing pseudogap behavior and measuring the London penetration depth.

Contribution

First NMR investigation of LaFeAsO(0.89)F(0.11) revealing spin fluctuations and superconducting parameters.

Findings

Detection of pseudogap behavior above Tc

Measurement of London penetration depth below Tc

Observation of low frequency spin fluctuations

Abstract

We report 19-F NMR investigation of the new high temperature superconductor LaFeAsO(0.89)F(0.11) (Tc ~ 28K). We demonstrate that low frequency spin fluctuations exhibit pseudo gap behavior above Tc. We also deduce the London penetration depth lambda from NMR line broadening below Tc.