Work

Line nodes in the energy gap of superconducting BaFe2(As1−xPx)2 single crystals as seen via penetration depth and thermal conductivity

Year: 2010

Type: article

Abstract: We report magnetic penetration depth and thermal-conductivity data for high-quality single crystals of ${\text{BaFe}}_{2}{({\text{As}}_{1\ensuremath{-}x}{\text{P}}_{x})}_{2}({T}_{c}=30\text{ }\text{K})$ which provide strong evidence that this material has line nodes in its energy gap. This is distinctly different from the nodeless gap found for $(\text{Ba},\text{K}){\text{Fe}}_{2}{\text{As}}_{2}$ which has similar ${T}_{c}$ and phase diagram. Our results indicate that repulsive electronic interactions play an essential role for Fe-based high-${T}_{c}$ superconductivity but that uniquely there are distinctly different pairing states, with and without nodes, which have comparable ${T}_{c}$.

Source: Physical Review B

DOI: 10.1103/physrevb.81.220501