Linear and quadratic piezoelectric coefficients of wurtzite III-V (GaP, InP, GaAs and InAs) semiconductors are calculated using ab-initio density functional theory. We show that the predicted magnitude of such coefficients is much larger than previously reported and of the same order of magnitude as those of III-N semiconductors. In order to show the applicability of wurtzite III-V semiconductors as piezoelectric materials, we model the bending distortion created on a nanowire by an atomic force microscope tip. We calculate the dependence of the piezoelectric properties of both homogeneous and core shell wurtzite III-V semiconductor structures on the induced deflection. We show that a number of combinations of III-V materials for the core and the shell of the nanowires can favor much increased voltage generation. We observe the largest core voltages in core/shell combinations of InAs/GaP, InP/GaP, GaP/InAs and GaP/InP which are predicted to be 3 orders of magnitude larger than the typical values of 73 V in homogeneous nanowires. Also considering properties such as voltage generation, bandgap discontinuity and mobility, III-V wurtzite core-shell nanowires are candidates for high performance components in piezotronics and nanogeneration.

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The piezoelectric effect in polar semiconductor has seen increased interest in recent years because of the prospect of exploiting semiconducting behavior and piezoelectric response, i.e. generating electric fields in response to pressure, in novel optoelectronic devices with applications as pressure sensors and energy harvesting. In this paper we review the basic concepts and recent findings related to the novel concept of non-linear piezoelectricity, which can be exploited in composite nanostructured materials to increase the piezoelectric response compared to bulk materials. Applications to light emitting diodes and nanowires will also be discussed. We will show how the non-linear theory of piezoelectricity can in some cases lead to opposite predictions compared to the classic linear theory.