Abstract: | The superconductor Sr2RuO4 has been thought for nearly twenty years to have a px+ipy order parameter, which would make Sr2RuO4 a two-dimensional electronic analogue of superfluid 3He. But definitive demonstration has proved difficult. Lifting the tetragonal symmetry of the crystal lattice should yield a characteristic response, by lifting the degeneracy between the two components of the superconductivity. To test this, we have constructed an apparatus capable of applying both compressive and tensile strains of up to 0.25%. Tc of Sr2RuO4 was found to increase strongly under both tensile and compressive strains along the crystallographic (100) directions, but shows very weak response to (110) strains. As well as advancing our understanding of Sr2RuO4, this technique has potential applicability to a wide range of problems in solid-state physics. |