Bending strain in 3D topological semi-metals
Résumé
Abstract We present an experimental set-up for the controlled application of strain gradients by mechanical piezoactuation on 3D crystalline microcantilevers that were fabricated by focused ion beam machining. A simple sample design tailored for transport characterization under strain at cryogenic temperatures is proposed. The topological semi-metal Cd 3 As 2 serves as a test bed for the method, and we report extreme strain gradients of up to 1.3 % μ m −1 at a surface strain value of ≈ 0.65 % at 4 K. Interestingly, the unchanged quantum transport of the cantilever suggests that the bending cycle does not induce defects via plastic deformation. This approach is a first step towards realizing transport phenomena based on structural gradients, such as artificial gauge fields in topological materials.