Low Power, Scalable Nanofabrication via Photon Upconversion

Qi Zhou; Hao-Chi Yen; Qizhen Lan; Arynn O. Gallegos; Manchen Hu; Kyle Frohna; Hannah Niese; Da Lin; Natalia Murrietta; Pournima Narayanan; Tracy H. Schloemer; Linda Pucurimay; Sebastian Fernández; Michael Seitz; Daniel N. Congreve

arXiv · 2508.16668

Low Power, Scalable Nanofabrication via Photon Upconversion

Qi Zhou·Hao-Chi Yen·Qizhen Lan·Arynn O. Gallegos·Manchen Hu·Kyle Frohna·Hannah Niese·Da Lin·Natalia Murrietta·Pournima Narayanan·Tracy H. Schloemer·Linda Pucurimay·Sebastian Fernández·Michael Seitz·Daniel N. Congreve

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Abstract

Micro- and nanoscale fabrication, which enables precise construction of intricate three-dimensional structures, is of foundational importance for advancing innovation in plasmonics, nanophotonics, and biomedical applications. However, scaling fabrication to industrially relevant levels remains a significant challenge. We demonstrate that triplet-triplet annihilation upconversion (TTA-UC) offers a unique opportunity to increase fabrication speeds and scalability of micro- and nanoscale 3D structures. Due to its nonlinearity and low power requirements, TTA-UC enables localized polymerization with nanoscale resolutions while simultaneously printing millions of voxels per second through optical parallelization using off-the-shelf light-emitting diodes and digital micromirror devices. Our system design and component integration empower fabrication with a minimum lateral feature size down to 230 nm and speeds up to 112 million voxels per second at a power of 7.0 nW per voxel. This combination of high resolution and fast print speed demonstrates that TTA-UC is a significant advancement in nanofabrication technique, evidenced by the fabrication of hydrophobic nanostructures on a square-centimeter scale, paving the way for industrial nanomanufacturing.

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Qi Zhou, Hao-Chi Yen, Qizhen Lan, Arynn O. Gallegos, Manchen Hu, Kyle Frohna, Hannah Niese, Da Lin, Natalia Murrietta, Pournima Narayanan, Tracy H. Schloemer, Linda Pucurimay, Sebastian Fernández, Michael Seitz, Daniel N. Congreve. 2025-08-21. Low Power, Scalable Nanofabrication via Photon Upconversion. https://arxiv.org/abs/2508.16668

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