6 papers · 1 filter
Visible Imaging of Incoherent 1200-nm Light via Triplet--Triplet Annihilation Upconversion
Pournima Narayanan, Rabeeya Hamid, Linda Pucurimay +13
Upconversion of low-energy photons to higher-energy photons provides an opportunity to surpass traditional limitations in fields such as 3D printing, photovoltaics, and photocataly…
All-passive upconversion of incoherent near-infrared light at intensities down to 10 W/cm
Rabeeya Hamid, Demeng Feng, Pournima Narayanan +10
Frequency upconversion, which converts low-energy photons into higher-energy ones, typically requires intense coherent illumination to drive nonlinear processes or the use of exter…
Preventing overfitting in infrared ellipsometry using temperature dependence: fused silica as a case study
Shenwei Yin, Jin-Woo Cho, Demeng Feng +6
Fitting oscillator models to variable-angle spectroscopic ellipsometry (VASE) data can lead to non-unique, unphysical results. We demonstrate using temperature-dependent trends to…
Self-referencing photothermal common-path interferometry to measure absorption of Si3N4 membranes for laser-light sails
Tanuj Kumar, Demeng Feng, Shenwei Yin +12
Laser-light sails are a spacecraft concept wherein lightweight "sails" are propelled by high-intensity lasers. We investigated the near-infrared absorption of free-standing membran…
Thermal runaway of silicon-based laser sails
Gregory R. Holdman, Gabriel R. Jaffe, Min Seok Jang +3
Laser sail-based spacecraft -- where a powerful earth-based laser propels a lightweight outer-space vehicle -- have been recently proposed by the Breakthrough Starshot Initiative a…
Passive frequency conversion of ultraviolet images into the visible using perovskite nanocrystals
Jad Salman, Mahesh K. Gangishetty, Bryan E. Rubio-Perez +8
We demonstrate a passive down-conversion imaging system that converts broadband ultraviolet light to narrow-band green light while preserving the directionality of rays, and thus e…