Critical divergence of the symmetric ($A_{1g}$) nonlinear elastoresistance near the nematic transition in an iron-based superconductor

Abstract

We report the observation of a nonlinear elastoresistivity response for the prototypical underdoped iron pnictide Ba(Fe${}_{0.975}$Co${}_{0.025}$)${}_2$As${}_2$. Our measurements reveal a large quadratic term in the isotropic ($A_{1g}$) electronic response that was produced by a purely shear ($B_{2g}$) strain. The divergence of this quantity upon cooling towards the structural phase transition reflects the temperature dependence of the nematic susceptibility. This observation shows that nematic fluctuations play a significant role in determining even the isotropic properties of this family of compounds.

References in corpus (1)

• Determination of the phase diagram of the electron doped superconductor Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$

Cited by in corpus (8)

• The relationship between transport anisotropy and nematicity in FeSe
• Elastocaloric signature of nematic fluctuations
• Quantitative characterization of short-range orthorhombic fluctuations in FeSe through pair distribution function analysis
• Elastoresistivity in the incommensurate charge density wave phase of BaNi${}_{\text{2}}$(As${}_{\text{1-x}}$P${}_{\text{x}}$)${}_{\text{2}}$
• Emerging symmetric strain response and weakening nematic fluctuations in strongly hole-doped iron-based superconductors
• Electronic nematicity in URu2Si2 revisited
• Measurements of elastoresistance under pressure by combining in-situ tunable quasi-uniaxial stress with hydrostatic pressure
• Increase of critical current density in FeSe superconductor by strain effect