Fig. 2: Effect of shear strain on Tc.
From: Direct evidence for the absence of coupling between shear strain and superconductivity in Sr2RuO4
a Assembly of shear piezo and Sr2RuO4 sample, attached on a bamboo holder with copper wires, to be inserted into a mutual-inductance coil set for measuring AC susceptibility. (b) Imaginary and (c) real parts of the AC susceptibility measured by the mutual-inductance method (sample S5, shear [110]). The colours represent the chronological order in which the measurements were taken, as indicated by the colourscale in (d). The Tc is detected by two different criteria: fitting a Lorentzian peak (dotted vertical line in (b)) or a sigmoid function (dashed vertical line in (c)). d Resulting changes in Tc as a function of voltage applied to the shear piezo: from the peak maximum in χ′′ (squares) and from the mid-point of the drop in \({\chi }^{{\prime} }\) (circles). We use filled (open) symbols to indicate points taken with increasing (decreasing) voltage. e Changes in Tc with shear strain applied along the [100], f [110], and g [001] crystalline directions of Sr2RuO4 using several piezo-sample assemblies. The schematics above each panel indicate the corresponding shear deformation of the Sr2RuO4 lattice. A linear regression is performed on each data set to illustrate the variation of the small slopes. The grey shaded regions, marked by the black arrows, indicate confidence intervals chosen to represent the scattering of the data of ± 0.6, ± 0.9, and ± 0.6 mK, respectively.
