Probing angle-resolved reflection signatures of intralayer and interlayer excitons in monolayer and bilayer MoS_(2)  

作　　者：Hanwei Hu Xuewen Zhang Xinyu Zhang Lishu Wu Vanessa Li Zhang Silin He Guangchao Shi Ting Yu Jingzhi Shang 

机构地区：[1]Institute of Flexible Electronics,Northwestern Polytechnical University,Xi’an 710129,China [2]School of Materials Science and Engineering,Nanyang Technological University,Singapore 639798,Singapore [3]School of Physics and Technology,Wuhan University,Wuhan 430072,China

出　　处：《Nano Research》2023年第5期7844-7850,共7页纳米研究（英文版）

基　　金：the National Natural Science Foundation of China(No.61904151);the Joint Research Funds of the Department of Science&Technology of Shaanxi Province and Northwestern Polytechnical University(No.2020GXLH-Z-020);the Fundamental Research Funds for the Central Universities of China,the National Key R&D Program of China(No.2021YFA1200800);the Start-up Funds of Wuhan University.

摘　　要：Strongly bound excitons in atomically thin transition metal dichalcogenides offer many opportunities to reveal the underlying physics of basic quasiparticles and many-body effects in the two-dimensional(2D)limit.Comprehensive reflection investigation on band-edge exciton transitions is essential to exploring wealthy light–matter interactions in the emerging 2D semiconductors,whereas angle-resolved reflection(ARR)characteristics of intralayer and interlayer excitons in 2D MoS_(2)layers remain unclear.Herein,we report ARR spectroscopic features of A,B,interlayer excitons in monolayer(ML)and bilayer(BL)MoS_(2)on three kinds of photonic substrates,involving distinct exciton–photon interactions.In a BL MoS_(2)on a protected silver mirror,the interlayer exciton with one-third amplitude of A exciton appears at 0.05 eV above the A exciton energy,exhibiting an angleinsensitive energy dispersion.When ML and BL MoS_(2)lie on a SiO_(2)-covered silicon,the broad trapped-photon mode weakly couples with the reflection bands of A and B excitons by the Fano resonance effect,causing the asymmetric lineshapes and the redshifted energies.After transferring MoS_(2)layers onto a one-dimensional photonic crystal,two high-lying branches of B-exciton polaritons are formed by the interactions between B excitons and Bragg photons,beyond the weak-coupling regime.This work provides ARR spectral benchmarks of A,B,interlayer excitons in ML and BL MoS_(2),gaining insights into the interpretation of light–matter interactions in 2D semiconductors and the design of their devices for practical photonic applications.

关 键 词：MoS_(2) EXCITON exciton–photon coupling exciton–polariton angle-resolved reflection 

分 类 号：O47[理学—半导体物理]