Strong and Tunable Light-Matter Interactions in Excitonic Semiconductors

The isolation of stable atomically thin two-dimensional (2D) materials on arbitrary substrates has led to a revolution in solid state physics and semiconductor device research over the past decade. A variety of other 2D materials (including semiconductors) with varying properties have been isolated raising the prospects for devices assembled by van der Waals forces.¹ Particularly, these van der Waals bonded semiconductors exhibit strong excitonic resonances² and large optical dielectric constants as compared to bulk 3D semiconductors. .<br/>First, I will focus on the subject of strong light-matter coupling in excitonic 2D semiconductors, namely chalcogenides of Mo and W. Visible spectrum band-gaps with strong excitonic absorption makes transition metal dichalcogenides (TMDCs) of molybdenum and tungsten as attractive candidates for investigating strong light-matter interaction formation of hybrid states.^3-5 We will present our recent work on the fundamental physics of light trapping in multi-layer TMDCs when coupled to plasmonic substrates.⁶<br/>Next, we will show the extension of these results to halide perovskites^{7, 8} and superlattices of excitonic chalcogenides.⁹ These hybrid multilayers offer a unique opportunity to tailor the light-dispersion in the strong-coupling regime.⁹ We will discuss the physics of strong light-matter coupling and applications of these structures. If time permits, I will also present our recent work on van der Waals semimetals,¹⁰ control of light in magnetic semiconductors¹¹ and extending some of these concepts to 1D carbon-nanotubes.¹²<br/>Our results highlight the vast opportunities available to tailor light-matter interactions¹¹ and building practical devices with 2D semiconductors. I will conclude with a broad vision and prospects for 2D materials in the future of semiconductor opto-electronics and photonics.<br/><br/><b>References:</b><br/>1. Jariwala, D.; et al. <i>ACS Nano </i><b>2014,</b> 8, (2), 1102–1120.<br/>2. Lynch, J.; Guarneri, L.; Jariwala, D.; van de Groep, J. <i>Journal of Applied Physics </i><b>2022,</b> 132, (9), 091102.<br/>3. Jariwala, D.; et al. <i>ACS Photonics </i><b>2017,</b> 4, 2692-2970.<br/>4. Brar, V. W.; Sherrott, M. C.; Jariwala, D. <i>Chemical Society Reviews </i><b>2018,</b> 47, (17), 6824-6844.<br/>5. Anantharaman, S. B.; Jo, K.; Jariwala, D. <i>ACS Nano </i><b>2021</b>.<br/>6. Zhang, H.; et al. Jariwala, D. <i>Nature Communications </i><b>2020,</b> 11, (1), 3552.<br/>7. Anantharaman, S. B.; et al. Jariwala, D. <i>Nano Letters </i><b>2021,</b> 21, (14), 6245-6252.<br/>8. Song, B.; et al. Jariwala, D. <i>ACS Materials Letters </i><b>2021,</b> 3, (1), 148-159.<br/>9. Kumar, P.; et al. Jariwala, D. <i>Nature nanotechnology </i><b>2022,</b> 17 182–189.<br/>10. Alfieri, A. D.; et al. Jariwala, D. <i>Advanced Optical Materials </i><b>2022</b>, 2202011.<br/>11. Zhang, H.; et al. Jariwala, D. <i>Nature Photonics </i><b>2022,</b> 16, 311-317.<br/>12. Lynch, J.; et al. Jariwala, D. <i>arXiv preprint arXiv:2304.08337 </i><b>2023</b>.