Fig. 1: Observation of emergent superelasticity in ceramic crystal GeSe.
From: Reversible shuffle twinning yields anisotropic tensile superelasticity in ceramic GeSe
a, Schematic of the stress–strain relationship for tensile and compressive superelastic deformations during the loading and unloading process. b, Schematic illustration of the interatomic potential as a function of atom distance. Here R denotes the distance between two interacting atoms, while σ represents the distance at which the potential energy equals zero. c, Crystal structure of GeSe (space group Pnma) viewed along the [100] direction. The purple and green balls represent Ge and Se atoms, respectively. d, Schematic diagram for the in situ uniaxial tensile equipment via the DT method. e, TEM image of GeSe nanobridges and diamond tensile gripper for the tensile test. f–h, In situ TEM images of the GeSe sample (sample A) before loading (f), at the beginning of superelasticity emergence (g) and at the maximum load (h). i, Stress–strain curve of a typical GeSe sample measured via the DT method. The critical strain for the emergence of superelasticity is roughly determined as the intersection of the tangent lines of the data in the linear elastic region and superelastic plateau region.
