Bringing the SWIR to Silicon with Upconversion Devices*

Infrared imaging, encompassing a spectrum of applications from healthcare to autonomous vehicles, has emphasized the need for advancing Near Infrared (NIR) and Short Wave Infrared (SWIR) detection capabilities. The potential to transform NIR and SWIR photons into detectable NIR photons via upconversion, compatible with prevalent silicon-based cameras, poses a formidable challenge to the current InGaAs sensor-dominated market. This dominance is characterized by intricate fabrication methodologies and heightened device costs, constraining the scalability of imaging solutions in this domain. Our research introduces a paradigm shift through the deployment of solid-state triplet-triplet annihilation upconversion via a charge-transfer state sensitization process. We present a pioneering single-step solution-processed deposition of a bulk heterojunction upconversion film employing organic semiconductors. Demonstrations across varied substrates, including glass and flexible mediums, underscore the versatility and potential of this material system for state-of-the-art upconversion applications.