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Abstract Wavelength‐selective absorbers (WS‐absorbers) are of interest for various applications, including chemical sensing and light sources. Lithography‐free fabrication of WS‐absorbers can be realized via Tamm plasmon polaritons (TPPs) supported by distributed Bragg reflectors (DBRs) on plasmonic materials. While multifrequency and nearly arbitrary spectra can be realized with TPPs via inverse design algorithms, demanding and thick DBRs are required for high quality‐factors (Q‐factors) and/or multiband TPP‐absorbers, increasing the cost and reducing fabrication error tolerance. Here, high Q‐factor multiband absorption with limited DBR layers (3 layers) is experimentally demonstrated by Tamm hybrid polaritons (THPs) formed by coupling TPPs and Tamm phonon polaritons when modal frequencies are overlapped. Compared to the TPP component, the Q‐factors of THPs are improved twofold, and the angular broadening is also reduced twofold, facilitating applications where narrow‐band and nondispersive WS‐absorbers are needed. Moreover, an open‐source algorithm is developed to inversely design THP‐absorbers consisting of anisotropic media and exemplify that the modal frequencies can be assigned to desirable positions. Furthermore, it is demonstrated that inversely designed THP‐absorbers can realize same spectral resonances with fewer DBR layers than a TPP‐absorber, thus reducing the fabrication complexity and enabling more cost‐effective, lithography‐free, wafer‐scale WS‐absorberss for applications such as free‐space communications and gas sensing.
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This content will become publicly available on December 1, 2026
Inverse designed aperiodic multilayer perfect absorbers for mid infrared enable tunability switchability and angular robustness
We present a class of inverse-designed, aperiodic multilayer graphene-based perfect absorbers operating in the mid-infrared spectrum (3–5 μm), a range vital for atmospheric transparency and advanced sensing. Our design leverages a fixed material sequence—graphene, PPSU dielectric spacers, and PbSe layers on a gold substrate—while achieving precise spectral tunability solely through layer thickness variation, enabling absorption peak control in 0.25 μm steps without any change in material composition. This physical tunability allows scalable fabrication of wavelength-specific devices using a single manufacturing process. We further demonstrate electrical switchability by dynamically modulating graphene’s chemical potential (µc from 0 eV to 1 eV), enabling absorption amplitude control and wavelength redshifting without structural alteration. The proposed absorber achieves > 99.9% efficiency using only five graphene layers in a compact ~ 2 μm stack, offering significant advantages in size, weight, power, and cost. Our hybrid micro-genetic inverse design algorithm enables this performance while preserving > 90% absorption at incidence angles up to 52°, supporting broad angular robustness. Extensive simulation and field distribution analyses confirm the role of plasmonic confinement and impedance matching. Additionally, we validate the design’s fabrication tolerance and benchmark its performance against recent state-of-the-art absorbers. By combining advanced inverse design with nanophotonic structures, our work advances the field of mid-infrared absorbers, providing a scalable and efficient platform for next-generation optical devices.
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- Award ID(s):
- 2406666
- PAR ID:
- 10612515
- Publisher / Repository:
- Sharif, Sarah
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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