Charge doping of iron-pnictide superconductors leads to collective pinning of flux vortices, whereas isovalent doping does not. Moreover, flux pinning in the charge-doped compounds is consistently described by the mean-free path fluctuations introduced by the dopant atoms, allowing for the extraction of the elastic quasiparticle scattering rate. The absence of scattering by dopant atoms in isovalently doped BaFe2(As1−xPx)2 is consistent with the observation of a linear temperature dependence of the low-temperature penetration depth in this material.
@article{arxiv.1005.2129,
title = {Charge doping-induced quasiparticle scattering in iron-pnictide superconductors as probed by vortex pinning},
author = {Cornelis Jacominus van der Beek and Marcin Konczykowski and Shigeru Kasahara and Takahito Terashima and Ryuji Okazaki and Takasada Shibauchi and Yuji Matsuda},
journal= {arXiv preprint arXiv:1005.2129},
year = {2015}
}