Near Unity Absorption in Van der Waals Semiconductors for Ultrathin Optoelectronics

TL;DR

This paper demonstrates near-unity broadband light absorption in ultrathin van der Waals semiconductors, enabling highly efficient optoelectronic devices by coupling to optical modes in heterostructures.

Contribution

It introduces a method to achieve near-unity absorption in sub-15 nm TMDCs through coupling with optical modes, advancing their use in high-efficiency optoelectronics.

Findings

Achieved near-unity broadband absorption in ultrathin TMDCs.

Fabricated Schottky junction devices with high optoelectronic performance.

Demonstrated coupling to strongly damped optical modes in heterostructures.

Abstract

We demonstrate near unity, broadband absorbing optoelectronic devices using sub-15 nm thick transition metal dichalcogenides (TMDCs) of molybdenum and tungsten as van der Waals semiconductor active layers. Specifically, we report that near-unity light absorption is possible in extremely thin (< 15 nm) Van der Waals semiconductor structures by coupling to strongly damped optical modes of semiconductor/metal heterostructures. We further fabricate Schottky junction devices using these highly absorbing heterostructures and characterize their optoelectronic performance. Our work addresses one of the key criteria to enable TMDCs as potential candidates to achieve high optoelectronic efficiency.