Superconducting penetration depth measurement and zero field muon spin relaxation experiments on Sr₂RuO₄ under uniaxial strain

To probe its superconducting order parameter, we have performed muon spin relaxation (muSR) measurements on samples of Sr₂RuO₄ placed under uniaxial stress. Previous studies on unstressed Sr₂RuO₄ have revealed enhanced relaxation in the superconducting state, which is interpreted as evidence for a chiral px ± ipy order parameter. With this order parameter, uniaxial stress is expected to induce a splitting between Tc and the onset of chirality. muSR requires large samples, so to perform these measurements, we have developed piezoelectric-based apparatus capable of applying forces of up to ~ 500 N.