Ultrasonic measurements have been performed on high quality single crystals of Sr2RuO4 across the superconducting transition temperature Tc (≈ 1.37 K). A discontinuous jump at Tc was observed in a longitudinal elastic modulus C11 as is seen in conventional superconductors, and the strain dependence of Tc was estimated from the jump by using the Ehrenfest relation. The uniaxial pressure dependence of Tc in Sr2RuO4 was found to be negative along the a axis and positive along the c axis, respectively. Thermodynamic analysis has cleanly shown that the superconductivity of Sr 2RuO4 is much affected by the deformation of RuO 2 planes. The strain effects on superconductivity are explained by large anisotropy of the lattice and electronic structure in Sr 2RuO4.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)