Hybridization in van der Waals epitaxy of PtSe2/h-BN and PtSe2/graphene heterostructures

TL;DR

This study compares the electronic properties of PtSe2 monolayers on h-BN and graphene substrates, revealing substrate-dependent hybridization effects and their implications for nanoelectronic applications.

Contribution

It provides a systematic analysis of how different substrates influence the electronic structure and hybridization in PtSe2 vdW heterostructures using ARPES and DFT.

Findings

Interlayer hybridization observed in PtSe2/graphene with minigap openings.

Valence band maximum position varies with substrate, at -0.9 eV (h-BN) and -0.55 eV (graphene).

Substrate plays a crucial role in the electronic properties of vdW heterostructures.

Abstract

Van der Waals (vdW) heterostructures, which combine bi-dimensional materials of different properties, enable a range of quantum phenomena. Here, we present a comparative study between the electronic properties of mono- and bi-layer of platinum diselenide (PtSe2) grown on hexagonal boron nitride (h-BN) and graphene substrates using molecular beam epitaxy (MBE). Using angle-resolved photoemission spectroscopy (ARPES) and density functional theory (DFT), the electronic structure of PtSe2/graphene and PtSe2/h-BN vdW heterostructures are investigated in systematic manner. In contrast to PtSe2/h-BN, the electronic structure of PtSe2/graphene reveals the presence of interlayer hybridization between PtSe2 and the graphene, which is evidenced by minigap openings in the {\pi}-band of graphene. Furthermore, our measurements show that the valence band maximum (VBM) of monolayer PtSe2 is located at the {\Gamma} point with different binding energies of about -0.9 eV and -0.55 eV relative to the Fermi level on h-BN and graphene and substrates, respectively. Our results represent a significant advance in the understanding of electronic hybridization between TMDs and different substrates, and they reaffirm the crucial role of the substrate in any nanoelectronic applications based on van der Waals heterostructures.