High-Pressure Vibrational and Optoelectronic Properties of Mono- and Multi-Layer Rhenium Disulfide

Rhenium disulfide (ReS₂) is a layered semiconductor of the transition metal dichalcogenide family, which are notable for their promising applications in two-dimensional electronics. ReS₂ possesses in-plane anisotropy and comparatively weak interlayer bonding that can be exploited for a range of device applications, including highly sensitive polarized light detectors and strain-robust electronic devices. The low-symmetry (triclinic) crystal structure also allows for examination of the material’s polarization-dependent lattice dynamics, which may offer insight into its anisotropic transport properties – an important consideration in ReS₂-based devices. In this study, we conduct angle-resolved polarized Raman spectroscopy under application of pressures up to 13 GPa in a diamond anvil cell to evaluate the strain response of the lattice dynamics in ReS₂. Additionally, we report the pressure dependence of the optical bandgap of both mono- and multi-layer samples using photoluminescence spectroscopy. Our results highlight the unique optoelectronic and vibrational strain response of mono- and multi-layer ReS₂ under pressure, and provide context for how ReS₂ could be implemented in next-generation electronic devices.