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arXiv · 2204.13768

Ultrastrong Coupling of Band-Nested Excitons in Few-Layer Molybdenum Disulphide

Aaron H. Rose·Taylor J. Aubry·Hanyu Zhang·Jao van de Lagemaat
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Abstract

The two-dimensional transition-metal dichalcogenides (2D TMDCs) are an intriguing platform for studying light-matter interactions because they combine the electronic properties of conventional semiconductors with the optical resonances found in organic systems. However, the coupling strengths demonstrated in strong exciton-polariton coupling remain much lower than those found in organic systems. In this paper, we take on a new approach by utilizing the large oscillator strength of the above-band gap C exciton in few-layer molybdenum disulphide ($\text{FL-MoS}_2$). We show a k-space Rabi splitting of 293 meV when coupling $\text{FL-MoS}_2$ C excitons to surface plasmon polaritons at room temperature. This value is 11% of the uncoupled exciton energy (2.67 eV or 464 nm), ~2x what is typically seen in the TMDCs, placing the system in the ultrastrong coupling regime. Our results take a step towards finally achieving the efficient quantum coherent processes of ultrastrong coupling in a CMOS-compatible system -- the 2D TMDCs -- in the visible spectrum.

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Aaron H. Rose, Taylor J. Aubry, Hanyu Zhang, Jao van de Lagemaat. 2022-04-28. Ultrastrong Coupling of Band-Nested Excitons in Few-Layer Molybdenum Disulphide. https://arxiv.org/abs/2204.13768

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