Nanophotonics Seminar - Day 1

"Strong and Tunable Light-Matter Interactions in Excitonic Materials and Devices"

Deep Jariwala

Department of Electrical and Systems Engineering, University of Pennsylvania

Abstract:

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. Particularly, these van der Waals bonded semiconductors exhibit strong excitonic resonances1 and large optical dielectric constants as compared to bulk 3D semiconductors. .

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.2-4 We will present our recent work on the light trapping in multi-layer TMDCs when coupled to reflective substrates.5 Next, I will show the extension of these results to superlattices of excitonic chalcogenides6, multilayer halide perovskites7-9 as well as metal organic chalcogenolates.10 These hybrid multilayers and materials offer a unique opportunity to tailor the light-dispersion in the strong to ultra-strong coupling regime. Finally, if time permits, I will discuss the physics of strong light-matter coupling and it's applications in phase modulator devices11, photovoltaic devices as well as control of light in magnetic semiconductors12 and extending some of these concepts to 1D carbon-nanotubes.13

Our results highlight the vast opportunities available to tailor light-matter interactions12 and building practical devices with 2D semiconductors. I will conclude with a broad vision and prospects for 2D and 1D materials in the future of semiconductor opto-electronics and photonics.4, 14

References:

(1) Lynch, J.; Jariwala, D. et al. Journal of Applied Physics 2022, 132 (9), 091102.

(2) Jariwala, D.; et al. ACS Photonics 2017, 4, 2692-2970.

(3) Brar, V. W.; Jariwala, D. Chemical Society Reviews 2018, 47 (17), 6824-6844

(4) Anantharaman, S. B.; Jo, K.; Jariwala, D. ACS Nano 2021, 15, 12628–12654.

(5) Zhang, H.; et al. Jariwala, D. Nature Communications 2020, 11 (1), 3552.

(6) Kumar, P.; et al. Jariwala, D. Nature nanotechnology 2022, 17 182–189.

(7) Anantharaman, S. B.; et al. Jariwala, D. Light: Science & Applications 2024, 13 (1), 1.

(8) Anantharaman, S. B.; et al. Jariwala, D. Nano Letters 2021, 21 (14), 6245-6252.

(9) Song, B.; et al. Jariwala, D. ACS Materials Letters 2021, 3 (1), 148-159.

(10) Anantharaman, S. B.; et al. Jariwala, D. Nature Photonics 2025.

(11) Lynch, J.; et al. Jariwala, D. Device 2025, 10.1016/j.device.2024.100639.

(12) Zhang, H.; et al. Jariwala, D. Nature Photonics 2022, 16, 311-317.

(13) Lynch, J.; et al. Jariwala, D. Nature Photonics 2024, 18 (11), 1176-1184.

(14) Song, S.; Rahaman, M.; Jariwala, D. ACS Nano 2024, 18, 10955–10978.

More about the Speaker:

Deep Jariwala is an Associate Professor and the Peter & Susanne Armstrong Distinguished Scholar in the Electrical and Systems Engineering as well as Materials Science and Engineering at the University of Pennsylvania (Penn). Deep completed his undergraduate degree in Metallurgical Engineering from the Indian Institute of Technology in Varanasi and his Ph.D. in Materials Science and Engineering at Northwestern University. Deep was a Resnick Prize Postdoctoral Fellow at Caltech before joining Penn to start his own research group. His research interests broadly lie at the intersection of new materials, surface science and solid-state devices for computing, opto-electronics and energy harvesting applications in addition to the development of correlated and functional imaging techniques. Deep's research has been widely recognized with several awards from professional societies, funding bodies, industries as well as private foundations, the most notable ones being the Optica Adolph Lomb Medal, the Bell Labs Prize, the AVS Peter Mark Memorial Award, IEEE Photonics Society Young Investigator Award, IEEE Nanotechnology Council Young Investigator Award, IUPAP Early Career Scientist Prize in Semiconductors, the SPIE Early career achievement award and the Alfred P. Sloan Fellowship. He has published over 150 journal papers with more than 22000 citations and holds several patents. He serves as the Associate Editor for ACS Nano Letters and has been appointed as a Distinguished Lecturer for the IEEE Nanotechnology Council for 2025.

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"Electrochemically Gated Oxides and Large-Area Fabrication for Nano-Optics"

Vivian Ferry

Chemical Engineering and Materials Science, University of Minnesota

Abstract:

This talk will discuss two classes of materials development for optical applications, that address two of the biggest challenges: dynamic tunability and large-scale manufacturing. Electrochemical ion insertion and removal is emerging as a powerful method to tune the optical properties of materials. The perovskite cobaltite La1-xSrxCoO3-δ (LSCO) is an exemplary system for electrochemical control, exhibiting wide electrical, magnetic, thermal, and optical tunability upon oxygen insertion and removal via electrolyte gating. This talk will discuss LSCO as a candidate material for dynamically tunable metamaterials and low-power, electrically tunable optical devices. The second part will discuss a new approach to roll-to-roll manufacturing of metamaterials that uses entirely additive processing. Techniques like nanoimprint lithography are cost-effective, roll-to-roll compatible methods for translating patterns to large areas, but transferring these patterns into functional materials often requires subtractive processes like etching or liftoff. We have recently developed a roll-to-roll process that combines nanoimprint with additive ink delivery, utilizing topographical discontinuous dewetting to localize inks only in the desired locations. The talk will discuss the process windows for achieving nanopatterning, which allows us to realize large-area nanopatterns of metals, dielectrics, and semiconductors, on flexible substrates.

More about the Speaker:

Vivian Ferry is an associate professor and the Ray D. and Mary T. Johnson/Mayon Plastics professor at the University of Minnesota in the Department of Chemical Engineering and Materials Science. She received her S. B. in Chemistry from the University of Chicago, her Ph.D. in Chemistry from the California Institute of Technology working with Prof. Harry Atwater, and was a postdoctoral fellow with Prof. Paul Alivisatos at Lawrence Berkeley National Laboratory. Her research focuses on light-matter interactions in nanoscale materials, and her specific research interests include light management in solar energy conversion, switchable metamaterials, and nanoscale chirality. She is the recipient of an NSF CAREER award, an Air Force Office of Scientific Research Young Investigator Award, the Marion Milligan Mason Award for women in the chemical sciences, the SPIE Early Career Achievement Award, and was named as one of Technology Review's 35 Innovators under 35.