Universal observation of multiple order parameters in cuprate superconductors

Abstract

The temperature dependence of the London penetration depth λwas measured for an untwined single crystal of YBa_2Cu_3O_{7-δ} along the three principal crystallographic directions (a, b, and c). Both in-plane components (λ_a and λ_b) show an inflection point in their temperature dependence which is absent in the component along the c-direction (λ_c). The data provide convincing evidence that the in-plane superconducting order parameter is a mixture of s+d-wave symmetry whereas it is exclusively s-wave along the c-direction. In conjunction with previous results it is concluded that coupled s+d-order parameters are universal and intrinsic to cuprate superconductors.

5 pages, 3 figures

Cited by in corpus (7)

• The electronic phase diagram of the LaO1-xFxFeAs superconductor
• Anisotropy of superconducting single crystal SmFeAsO_(0.8)F_(0.2) studied by torque magnetometry
• Fermi surface and order parameter driven vortex lattice structure transitions in twin-free YBa2Cu3O7
• Superconducting electronic state in optimally doped YBa2Cu3O7-d observed with laser-excited angle-resolved photoemission spectroscopy
• Nodeless superconductivity in the infinite-layer electron-doped Sr_0.9La_0.1CuO_2 cuprate superconductor
• Oxygen-isotope effect on the superconducting gap in the cuprate superconductor Y_{1-x}Pr_xBa_2Cu_3O_{7-δ}
• Effects of phonon interaction on the pairing in the high-T$c$ superconductors