This summer practice focuses on the nanofabrication of all-dielectric phase-gradient metasurfaces optimized for thermal imaging in the long-wave infrared (LWIR) spectrum. By utilizing arrays of subwavelength silicon nanopillars to manipulate the optical wavefront, these flat, ultra-thin devices aim to replace bulky and heavy refractive lenses commonly used in medical diagnostics and surveillance. The objective of this practice is to provide students with hands-on experience in the precise realization of these designs using advanced semiconductor nanofabrication techniques available at the Kaunas University of Technology Institute of Materials Science cleanroom. The student will learn the design principles of high-index dielectric metasurfaces and acquire practical skills in the fabrication process, including electron beam lithography (EBL) for pattern definition, mask transfer techniques, and cryogenic deep reactive ion etching (cryo-DRIE) to achieve high-aspect-ratio vertical structures. Furthermore, the student will characterize the nanostructures using scanning electron microscopy (SEM) and integrate the fabricated metalens with a microbolometer camera to assemble a compact thermal microscope. Throughout the practice, students will work under supervision to ensure safety and efficiency. It is aimed to validate the potential of planar devices to achieve diffraction-limited focusing in thermal applications. By the end of the project, the student will have documented successful fabrication parameters and demonstrated the magnifying capabilities of the metalens. This practice is suited for students with a background in physics, engineering, or materials science who have a solid understanding of wave optics and are interested in the intersection of photonics and nanotechnology.
Project results:
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Period of project implementation: 2026-07-01 - 2026-08-31
Project coordinator: Kaunas University of Technology
