The impact of hBN layers on guided exciton–polariton modes in WS2 multilayers
Author:
Lee Ho Seung1, Sung Junghyun1, Shin Dong-Jin1, Gong Su-Hyun1ORCID
Affiliation:
1. Department of Physics , Korea University , Seoul , 02841 , South Korea
Abstract
Abstract
Guided exciton–polariton modes naturally exist in bare transition metal dichalcogenide (TMDC) layers due to self-hybridization between excitons and photons. However, these guided polariton modes exhibit a limited propagation distance owing to the substantial exciton absorption within the material. Here, we investigated the impact of hexagonal boron nitride (hBN) layers on guided exciton–polariton modes in WS2 multilayers. By integrating hBN layers, we demonstrate a notable enhancement in the quality of guided exciton–polariton modes. The hBN layers can reduce substrate surface roughness and provide surface protection for the WS2 layer, mitigating inhomogeneous broadening of the exciton resonance. Consequently, we experimentally observed that the propagation distance of polariton modes substantially increased with hBN layers. Additionally, the polariton spectrum broadened due to efficient exciton relaxation to the polariton states at lower energies. Comparison with simulation data emphasizes that the observed improvements are primarily attributed to enhanced exciton quality. The promising outcomes with hBN encapsulation suggest its potential to overcome strong excitonic losses of the guided exciton polariton in implementing nanophotonic devices. Furthermore, this approach provides a new avenue for exploring the novel physics of guided exciton–polariton modes and their potential applications in polariton-based all-optical integrated circuits.
Funder
Samsung Science and Technology Foundation National Research Foundation of Korea
Publisher
Walter de Gruyter GmbH
Subject
Electrical and Electronic Engineering,Atomic and Molecular Physics, and Optics,Electronic, Optical and Magnetic Materials,Biotechnology
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