Absence of superconductivity in hole-dopedBaFe2−xCrxAs2single crystals
Journal Articles
Overview
Research
Identity
Additional Document Info
View All
Overview
abstract
We investigate the physical properties and electronic structure upon
Cr-doping in the iron arsenide layers of BaFe2As2. This form of hole-doping
leads to suppression of the magnetic/structural phase transition in
BaFe2-xCrxAs2 for x > 0, but does not lead to superconductivity. For various x
values, temperature dependence of the resistivity, specific heat, magnetic
susceptibility, Hall coefficient, and single crystal x-ray diffraction data are
presented. The materials show signatures of approaching a ferromagnetic state
with x, including a metamagnetic transition for x as little as 0.36, an
enhanced magnetic susceptibility, and a large Sommerfeld coefficient. Such
results reflect renormalization due to spin fluctuations and they are supported
by density functional calculations at x = 1. Calculations show a strong
interplay between magnetic ordering and chemical ordering of Fe and Cr, with a
ferromagnetic ground state. This ferromagnetic ground state is explained in
terms of the electronic structure. The resulting phase diagram is suggestive
that superconductivity does not derive simply from the suppression of the
structural/magnetic transitions.
