Orthorhombic Distortion at the Superconducting Transition in Y<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi mathvariant="normal">Ba</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi mathvariant="normal">Cu</mi></mrow><mrow><mn>3</mn></mrow></msub></mrow></math><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi mathvariant="normal">O</mi></mrow><mrow><mn>7</mn></mrow></msub></mrow></math>: Evidence for Anisotropic Pairing

P. M. Horn; D. T. Keane; G. A. Held; J. L. Jordan-Sweet; D. L. Kaiser; F. Holtzberg; T. M. Rice

doi:10.1103/PhysRevLett.59.2772

Orthorhombic Distortion at the Superconducting Transition in Y ${Ba}_{2}$ ${Cu}_{3}$ $O_{7}$ : Evidence for Anisotropic Pairing

P. M. Horn, D. T. Keane, G. A. Held, J. L. Jordan-Sweet, D. L. Kaiser, F. Holtzberg, and T. M. Rice

Phys. Rev. Lett. 59, 2772 – Published 14 December 1987

Abstract

We report the results of a high-resolution x-ray scattering study of the structure of Y ${Ba}_{2}$ ${Cu}_{3}$ $O_{7}$ as a function of temperature. We find that there is an anomaly in the orthorhombic splitting, $b - a$ , near the superconducting transition, whereas there is little or no anomaly in the unit-cell volume. Our results suggest that the superconducting wave function has a uniaxial anisotropy within the $a - b$ plane.