Flexoelectric manipulation of ferroelectric polarization in self-strained tellurium

Abstract

<p>Beyond conventional ferroelectric compounds, the realization of single-element ferroelectricity expands the scope of ferroelectric materials and diversifies polarization mechanisms. However, strategies for manipulating ferroelectric dipoles in elemental ferroelectrics remain underexplored, limiting their broader applications. Here, we introduce a universal flexoelectric manipulation strategy to tune the ferroelectric and piezoelectric polarization of one-dimensional self-strained tellurium (Te) ferroelectrics. A substantial flexoelectric field of 9.55 microcoulombs per square centimeter was observed in self-strained Te, inducing a polarization rotation of 18°, comparable to the typical 15° rotation in ferroelectric PbTiO₃ compounds. This substantial polarization rotation enhances ferroelectric coercivity by 165% and piezoelectric responses by 75% compared to unstrained Te. Moreover, the flexoelectric manipulation of ferroelectric polarization demonstrated improved energy harvesting performance at the device level, surpassing most existing counterparts. Our findings highlight the crucial role of flexoelectricity-ferroelectricity coupling in developing high-performance single-element electromechanical devices and ferroelectronics.<br></p>