High-performance piezotronic quantum wells by tuning the quantum-confined Stark effect

Abstract

Recent advances in quantum piezotronics have highlighted the potential of strain-induced polarization fields to modulate quantum transport properties and manipulate quantum states in nanodevices. In this work, we theoretically investigate the effect of strain-induced polarization field on the quantum-confined Stark effect (QCSE) in a piezotronic device based on AlGaN/GaN quantum wells. By applying strain, we investigate fundamental properties such as interband transition energy, electron–hole wavefunction overlap, and aluminum composition dependence. The results demonstrate that the piezotronic effect enables effective modulation of carrier recombination. By enhancing the QCSE, the photodetector can achieve an ultrahigh responsivity of 1.8 × 106 A/W, representing a 170% improvement under a stress of −20 GPa. This work provides guidance for the design of high-efficiency optoelectronic devices and enriches the theoretical foundation of quantum piezotronics and piezo-phototronics.