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Updated: Aug 30, 2025

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Layer-Number Engineered Momentum-Indirect Interlayer Excitons with Large Spectral Tunability
Wendian Yao1, Dong Yang1, Yingying Chen1
1School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China.
Abstract:
Interlayer excitons (IXs) in type II van der Waals (vdW) heterostructures are equipped with an oriented permanent dipole moment and long lifetime and thus would allow promising applications in excitonic and optoelectronic devices. However, based on the widely studied heterostructures of transition-metal dichalcogenides (TMDs), IX emission is greatly influenced by the lattice mismatch and geometric misalignment between the constituent layers, increasing the complexity of the device fabrication. Here, we report on the robust momentum-indirect IX emission in TMD/two-dimensional (2D) perovskite vdW heterostructures, which were fabricated without considering the orientation arrangement or momentum mismatch. The IXs show a large diffusion coefficient of ∼10 cm2 s-1, and importantly the IX emission energy can be widely tuned from 1.3 to 1.6 eV via changing the layer number of the 2D perovskite or the thickness of TMD flakes, shedding light on the applications of vdW interface engineering to broad-spectrum optoelectronics.
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