Strain-engineering the anisotropic electrical properties of low-symmetry bilayer GeSe

Abstract

As an isostructural analog of black phosphorus, GeSe has attracted considerable attention recently due to its intriguing in-plane anisotropic optical, vibrational, and electrical properties stemming from the low-symmetry two-dimensional crystal structure. However, there has been no report about the anisotropy tuning of GeSe, hampering its further applications in optoelectronics and electronics. Here, we systematically investigate the change of electronic properties of the bilayer GeSe with different stacked crystal structures under strain through first-principles calculation. Notably, the anisotropy of electron effective mass can be controlled and even rotated by 90° in a slipping process of one crystallographic period along the armchair direction. These plentiful strain-engineering properties of the bilayer GeSe would render it useful for the exploration of novel GeSe-based optoelectronic and electronics applications.