AC Elastoresistivity and Elastocaloric Measurements of Cu_xTiSe₂

TiSe₂ is a transition metal dichalcogenide whose triple-q charge density wave is suppressed when it is intercalated with Cu or under hydrostatic pressure, revealing a superconducting dome. The charge density wave phase exhibits behaviors consistent with chiral symmetry breaking, but the driving mechanism and character of this emergent chirality remain a topic of hot discussion. Measurements of the anisotropic elastoresistivity coefficient of Cu_xTiSe₂ reveal a rapid increase in E_g strain response around the onset of the charge density wave, resembling the large diverging nematic susceptibility in iron based superconductors. This resemblance indicates strong fluctuations associated with broken rotational symmetry, motivating further studies of the strain response in Cu_xTiSe₂ which may serve to elucidate the structure of the charge density wave and its relationship to superconductivity. In this talk, we present measurements of the AC elastoresistivity and the elastocaloric effect of Cu_xTiSe₂ under large tunable DC bias strains, which reveals the entropy landscape and a highly nonlinear strain response of this system.