The angular dependences of the resistivity ρ(θ) in magnetic field applied to the ab-plane have been measured on electron doped Nd1.86Ce0.14CuO4 single crystals, where θ is the angle between the direction of a magnetic field H and of [0 1 0]. The obtained ρ(θ) shows the twofold anisotropy with a sharp dip that appears when the magnetic field is applied parallel to the direction of [1 0 0] or [0 1 0]. It is considered that the sharp dip originates from the Josephson vortex pinning by the estimation of the activation energy of the vortex. This absence of the fourfold symmetry of ρ(θ) in the ab-plane shows a possibility that the superconducting energy gap does not have d-wave pairing symmetry in the Nd-Ce-Cu-O system.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering