$\mu$SR measurements on Sr${}_2$RuO${}_4$ under $⟨110⟩$ uniaxial stress

Muon spin rotation/relaxation ($\mu$SR) and polar Kerr effect measurements provide evidence for a time-reversal symmetry breaking (TRSB) superconducting state in Sr${}_2$RuO${}_4$. However, the absence of a cusp in the superconducting transition temperature ($T_{\mathrm{c}}$) vs. stress and the absence of a resolvable specific heat anomaly at TRSB transition temperature ($T_{\mathrm{T}\mathrm{R}\mathrm{S}\mathrm{B}}$) under uniaxial stress challenge a hypothesis of TRSB superconductivity. Recent $\mu$SR studies under pressure and with disorder indicate that the splitting between $T_{\mathrm{c}}$ and $T_{\mathrm{T}\mathrm{R}\mathrm{S}\mathrm{B}}$ occurs only when the structural tetragonal symmetry is broken. To further test such behavior, we measured $T_{\text{c}}$ through susceptibility measurements, and $T_{\text{TRSB}}$ through $\mu$SR, under uniaxial stress applied along a $⟨110⟩$ lattice direction. We have obtained preliminary evidence for suppression of $T_{\text{TRSB}}$ below $T_{\text{c}}$, at a rate much higher than the suppression rate of $T_{\text{c}}$.