Dynamic model for piezotronic and piezo-phototronic devices under low and high frequency external compressive stresses

摘要

In this work, we aim to establish a theoretical method for modelling the dynamic characteristics of piezotronics and piezo-phototronic devices. By taking the simplest piezotronic device, PN junction as an example, we combine the small signal model and the unified approach to investigate its diffusion capacitance and conductance when it is under both low and high frequency external compressive stresses. This approach is different from the traditional considerations that treat the piezopotential as a static value. Furthermore, we expand the theory into piezo-phototronic devices, e.g., a light emitting diode. The dynamic recombination rate and light emitting intensity are quantitatively calculated under different frequencies of external compressive stresses.