Inducing ferroelastic domains in single-crystal \nCsPbBr3\n perovskite nanowires using atomic force microscopy

Abstract

Understanding and controlling the formation and dynamics of ferroelastic domains can be key to enhance metal halide perovskite device performance, but established methods lack spatial control at the level of single domains. Here, the authors induced the formation of ferroelastic domains in CsPbBr${}_{3}$ nanowires using an atomic force microscope tip, and studied the structural changes using nanofocused x-ray diffraction with a 60-nm beam. The applied stress locally induced lattice tilts that define room temperature-stable ferroelastic domains, which spread spatially and terminated at {112}-type domain walls. While pristine regions show an orthorhombic (004) reflection; regions exposed to higher forces exhibit {220}-type reflections.