High performance piezotronic logic nanodevices based on GaN/InN/GaN topological insulator

Piezotronics and piezo-phototronics have received increasing attention in flexible energy-harvesting devices, self-powered sensor systems utilizing piezoelectric semiconductor materials, such as ZnO, GaN and monolayer MoS2. Piezoelectric potentials induced by the externally applied strain can effectively control the generation, recombination and transport of the charge carriers for achieving high-performance devices. In this study, we describe the piezotronics effect on the GaN/InN/GaN quantum well, which can induce performances resembling those of topological insulators by a piezoelectric field polarized under the externally applied mechanical strain. The transport properties of bulk and edge states of this quantum well device have been investigated by calculating the electron density distribution under different widths of the quantum point contact (QPC), which is the origin of more conductance plateaus. In addition, we postulate the mechanical-electronic logic operation mechanisms based on the piezotronics effect adjusting the transport of edge states in the quantum well device. Fundamental logic units such as NOT, NAND and NOR gates have been innovatively designed for performing the logic computation functions from external mechanical stimuli. The logic nanodevices based on the topological insulator have near zero-power consumption and ultrahigh ON/OFF ratio. This work provides a deep insight into the piezotronics effect on the transport of bulk and edge states of the quantum well device, and offers novel solutions to design high-performance low-power mechanical-electronic logic devices.