Nematicity in the superconducting mixed state of strain detwinned underdoped Ba(Fe1−xCox)2As2

J SCHMIDT; VICTORIA BECKERIS; GUSTAVO S LOZANO; M V BORTULE; M MARZIALI BERMÚDE; C. W. HICKS; P. C. CANFIELD; E FRADKIN; GABRIELA PASQUINI

PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS

APS

Año: 2019

0163-1829

Evidence of nematic effects in the mixed superconducting phase of slightly underdoped Ba(Fe1−xCox )2As2 isreported. We have found strong in-plane resistivity anisotropy for crystals in different strain conditions. For thesecompositions, there is no magnetic long-range order, so the description may be ascribed to the interplay betweenthe superconducting and nematic order parameters. A piezoelectric-based apparatus is used to apply tensile orcompressive strain to tune nematic domain orientation in order to examine intrinsic nematicity. Measurements aredone under a rotating magnetic field, and the analysis of the angular dependence of physical quantities identifiesthe cases in which the sample is detwinned. Furthermore, the angular dependence of the data allows us to evaluatethe effects of nematicity on the in-plane superconductor stiffness. Our results show that although nematicitycontributes in a decisive way to the conduction properties, its contributions to the anisotropy properties of thestiffness of the superconducting order parameter is not as significant in these samples.