TY - JOUR

T1 - Dielectric Function of 2D Tungsten Disulfide in Homo‐and Heterobilayer Stacking

AU - Peci, Ermes

AU - Magnozzi, Michele

AU - Ramó, Lorenzo

AU - Ferrera, Marzia

AU - Convertino, Domenica

AU - Pace, Simona

AU - Orlandini, Giorgio

AU - Sharma, Apoorva

AU - Milekhin, Ilya

AU - Salvan, Georgeta

AU - Coletti, Camilla

AU - Zahn, Dietrich R.T.

AU - Bisio, Francesco

AU - Canepa, Maurizio

N1 - Acknowledgements: The research leading to these results has received funding from Compagnia di San Paolo (project STRATOS) and Ministero dell'Istruzione, dell'Universitá e della Ricerca: PRIN 2017 grant number 2017KFY7XF, Dipartimenti di Eccellenza 2018–2022, and the European Union Horizon 2020 Programme under grant agreement no. 881603 Graphene Core 3. The authors acknowledge support from DAAD (German Academic Exchange Service) Research Grants—Short-Term Grants, 2021 (57552336).

PY - 2023/1/26

Y1 - 2023/1/26

N2 - The opto-electronic properties of semiconducting 2D materials can be flexibly manipulated by engineering the atomic-scale environment. This can be done by including 2D materials in tailored van der Waals (vdW) stacks, whose optical response is a function of the number and the type of adjacent 2D layers. This work reports a systematic investigation of the dielectric function of 2D semiconducting WS2 in various stacking configurations: monolayer, 3R/2H homobilayer, and WS2/MoS2 heterobilayer. Reliable, Kramers–Kronig-consistent dielectric functions are obtained for WS2 in each configuration by means of spectroscopic ellipsometry (SE) and related parametric optical modeling in a wide spectral range (1.55–3.10 eV). The results of SE are combined with photoluminescence and absorbance spectra to identify the spectral position of the main excitonic features in WS2, which manifest sizable redshifts depending on the stacking configuration. These results represent a consistent reference set for the dielectric function of WS2 in vdW stacking configurations of particular interest for the scientific and technological field, and can be fruitfully exploited for reliable predictions of the optical response of WS2-containing systems.

AB - The opto-electronic properties of semiconducting 2D materials can be flexibly manipulated by engineering the atomic-scale environment. This can be done by including 2D materials in tailored van der Waals (vdW) stacks, whose optical response is a function of the number and the type of adjacent 2D layers. This work reports a systematic investigation of the dielectric function of 2D semiconducting WS2 in various stacking configurations: monolayer, 3R/2H homobilayer, and WS2/MoS2 heterobilayer. Reliable, Kramers–Kronig-consistent dielectric functions are obtained for WS2 in each configuration by means of spectroscopic ellipsometry (SE) and related parametric optical modeling in a wide spectral range (1.55–3.10 eV). The results of SE are combined with photoluminescence and absorbance spectra to identify the spectral position of the main excitonic features in WS2, which manifest sizable redshifts depending on the stacking configuration. These results represent a consistent reference set for the dielectric function of WS2 in vdW stacking configurations of particular interest for the scientific and technological field, and can be fruitfully exploited for reliable predictions of the optical response of WS2-containing systems.

KW - dielectric function

KW - dielectric screening

KW - ellipsometry

KW - tungsten disulfide

KW - van der Waals bilayer

UR - https://www.mendeley.com/catalogue/5c33529f-3969-3b07-8ab3-7f94cf2030eb/

U2 - 10.1002/admi.202201586

DO - 10.1002/admi.202201586

M3 - Article

VL - 10

JO - Advanced Materials Interfaces

JF - Advanced Materials Interfaces

SN - 2196-7350

IS - 3

M1 - 2201586

ER -