Heterostructure-induced modulation of optical anisotropy in ReSe2

Abstract

The precise identification of the optical anisotropy principal axis and the controlled modulation of optical anisotropy in low-dimensional semiconductor materials are critical for advancing polarization optoelectronic devices. This paper introduces an enhanced reflectance difference spectroscopy imaging technique that can simultaneously determine the optical anisotropy principal axis of ReSe2 across a range of thicknesses, from monolayers to bulk forms. Additionally, it presents a method for modulating the optical anisotropy principal axis of strongly anisotropic materials by overlaying them with isotropic materials via mechanical exfoliation, thereby creating van der Waals heterostructures. Overall, this research not only establishes a straightforward and practical optical technique for accurately identifying the optical anisotropy principal axis but also offers a viable strategy for controlling optical anisotropy.