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arXiv · 2311.06022

Dipolar interactions enhanced by two-dimensional dielectric screening in few-layer van der Waals structures

Yuhang Hou·Hongyi Yu
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Abstract

We theoretically examined how the dielectric screening of two-dimensional layered materials affects the dipolar interaction between interlayer excitons in few-layer van der Waals structures. Our analysis indicates that the dipolar interaction is largely enhanced by two-dimensional dielectric screening at an inter-exciton separation of several nanometers or larger. The underlying mechanism can be attributed to the induced-charge densities in layered materials, which give rise to induced-dipole densities at large distances with directions parallel to that of the interlayer exciton. The interaction between quadrupolar excitons in trilayer structures are found to be enhanced even larger, with a magnitude one to two orders stronger than that without 2D dielectric screening. The strengths of these dipolar and quadrupolar interactions can be further tuned by engineering the dielectric environment.

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Yuhang Hou, Hongyi Yu. 2023-11-10. Dipolar interactions enhanced by two-dimensional dielectric screening in few-layer van der Waals structures. https://doi.org/10.1088/2053-1583%2Fad2525

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