A 1D nonlinear model for piezoelectric semiconductor fibers incorporating thermal and thermoelectric effects

Abstract

This paper studies multi-physical fields in a piezoelectric semiconductor (PS) fiber with consideration of heat conduction, pyroelectric, and thermoelectric effects. Based on the three-dimensional (3D) framework of piezoelectricity, drift–diffusion theory, Seebeck effect, and Peltier effect, we develop a highly nonlinear one-dimensional (1D) model that incorporates axial deformation, axial variations of the electric field, the redistribution of carriers, and temperature deviation. Combining the 1D nonlinear governing equations and the corresponding boundary conditions, the influence of the thermoelectric coefficients and axial forces on electrostatic potential, carrier redistribution, and temperature variation are solved numerically. Due to the nonlinearity of the model, these solutions are observed without symmetry or asymmetry. Our research shows that the temperature will increase near the action point of the axial force. Therefore, the temperature deviation in the fiber can be controlled by applying axial force at different points. Finally, we examine how the axial forces applied in the fiber affect the current–voltage relation. The presented study provides a potential application for mechanical switches, sensors, or thermal control for PSs.