Work

Advancing excited-state properties of two-dimensional materials using a dielectric-dependent hybrid functional

Year: 2025

Type: article

Abstract: Predicting accurate band gaps and optical properties of lower-dimensional materials, including two-dimensional van der Waals (vdW) materials and their heterostructures, remains a challenge within density functional theory (DFT) due to their unique screening compared to their bulk counterparts. Additionally, accurate treatment of the dielectric response is crucial for developing and applying screened-exchange dielectric-dependent range-separated hybrid functionals (SE-DD-RSH) for vdW materials. In this work, we introduce a SE-DD-RSH functional to the 2D vdW materials like MoS 2 , WS 2 , h BN , black phosphorus (BP), and β − InSe . By accounting for in-plane and out-of-plane dielectric responses, our method achieves accuracy comparable to advanced many-body techniques like G 0 W 0 and BSE@ G 0 W 0 at a lower computational cost. We demonstrate improved band gap predictions and optical absorption spectra for both bulk and layered structures, including some heterostructures like MoS 2 / WS 2 . This approach offers a practical and precise tool for exploring electronic and optical phenomena in 2D materials, paving the way for efficient computational studies of layered systems.

Source: Physical review. B./Physical review. B

DOI: 10.1103/8vvn-k9p3

Authors: Arghya Ghosh, Subrata Jana, Manoar Hossain, Dimple Rani, Szymon Śmiga, Prasanjit Samal