Details

Autor(en) / Beteiligte

• Xin, Ming
• Lan, Wenze
• Bai, Qinghu
• Huang, Xin
• Watanabe, Kenji
• Taniguchi, Takashi
• Wang, Gang
• Gu, Changzhi
• Liu, Baoli

Titel

The trilayer exciton emission in WSe2/WS2/MoS2 van der Waals heterostructures

Ist Teil von

• Applied physics letters, 2022-10, Vol.121 (14)

Ort / Verlag

Melville: American Institute of Physics

Erscheinungsjahr

2022

Quelle

American Institute of Physics

Beschreibungen/Notizen

• In this Letter, we present the experimental observation of trilayer exciton emission in the WSe2/WS2/MoS2 heterostructures by photoluminescence spectroscopy at a low temperature of ∼10 K. It is found that the trilayer exciton has a lower exciton binding energy than that in the WSe2/MoS2 heterobilayer due to the insertion of monolayer WS2, which is manifested by the blueshift of this trilayer exciton peak relative to the bilayer exciton. Through the measurements of the exciton peak position as a function of excitation power, the trilayer excitons exhibited the density-dependent repulsive interaction among them, and the reduction of binding energy ∼8 meV is deduced. Moreover, the trilayer exciton has a longer lifetime than the bilayer exciton, resulting from the reduction of electron–hole wavefunction overlap.