Pressure-driven metallization with significant changes of structural and photoelectric properties in two-dimensional EuSbTe3

Abstract

Two-dimensional materials are widely considered to be highly promising for the development of photodetectors. To improve the performance of these devices, researchers often employ techniques such as defect engineering. Herein, pressure is employed as a clean and novel means to manipulate the structural and physical properties of EuSbTe₃, an emerging two-dimensional semiconductor. The experimental results demonstrate that the structural phase transformation of EuSbTe₃ occurs under pressure, with an increase in infrared reflectivity, a band gap closure, and a metallization at pressures. Combined with X-ray diffraction (XRD) and Raman characterizations, it is evident that the pressure-driven transition from semiconductor Pmmn phase to metallic Cmcm phase causes the disappearance of the charge density wave. Furthermore, at a mild pressure, approximately 2 GPa, the maximum photocurrent of EuSbTe₃ is three times higher than that at ambient condition, suggesting an untapped potential for various practical applications.

Graphical abstract