Upper critical field of the 122-type iron pnictide superconductors

Abstract

The upper critical fields ($H_{c2}$) of the single crystals $(\mathrm{Sr},\mathrm{Na})\mathrm{F}{\mathrm{e}}_2\mathrm{A}{\mathrm{s}}_2$ and $\mathrm{B}{\mathrm{a}}_{0.55}{\mathrm{K}}_{0.45}\mathrm{F}{\mathrm{e}}_2\mathrm{A}{\mathrm{s}}_2$ were determined by means of measuring the electrical resistivity, ${\rho }_{xx}({\mu }_{0}H)$, using the facilities of pulsed magnetic field at Los Alamos. In general, these compounds possess a very large upper critical field ($H_{c2}(0)$) with a weak anisotropic effect. The detailed curvature of $H_{c2}(T_c)$ may depend on the magnetic field orientation and the sample compositions. We argue that such a difference mainly results from the multi-band effect, which might be modified via doping.

4 pages,4 figures, accepted by J. Phys. Chem. Solids

References in corpus (11)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Superconductivity at 43 K in Samarium-arsenide Oxides $SmFeAs{O}_{1-x}{F}_x$
• Observation of Fermi-surface-dependent nodeless superconducting gaps in Ba0.6K0.4Fe2As2
• Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides
• Nearly Isotropic superconductivity in (Ba,K)Fe2As2
• Superconductivity up to 29 K in SrFe2As2 and BaFe2As2 at high pressures
• Spin-singlet superconductivity with multiple gaps in PrO0.89F0.11FeAs
• Transport and anisotropy in single-crystalline SrFe${}_2$As${}_2$ and $A_{0.6}$K${}_{0.4}$Fe${}_2$As${}_2$ ($A$ = Sr, Ba) superconductors
• Pressure-induced superconductivity in single crystal CaFe2As2
• Electronic Structure of Fe-Based Superconductors
• Psuedo-isotropic upper critical field in cobalt-doped SrFe2As2 epitaxial films

Cited by in corpus (1)

• Large increase of the anisotropy factor in the overdoped region of Ba(Fe${}_{1-x}$Ni${}_x$)${}_2$As${}_2$ as probed by fluctuation spectroscopy