Abstract
Wavelength-selective light absorbers, emitters, or spectroscopic energy transducers for light, are widely utilized in our society by providing wide variety of applications in lighting, solar energy harvesting, remote sensing, and label free bio-sensing. With the combination of novel and efficient phosphor materials and simple micro- and nano-architectures, such as Fabri-Perot resonator1,2 and whispering gallery resonatores3, and polaritonic grating absorbers4, one can engineer spectroscopic feature in wavelength conversion and light amplification which will be useful for lighting application and photonic encryption. Fluorescent carbon dots/carbonized polymer dots (CDs/ CPDs) are promising materials that exhibit unique luminescence in the visible-to near-infrared wavelength region. These metal-free novel phosphor materials have gained significant interest because of their unique optical properties, photo stability, low cost, and low toxicity, thus being utilized in widespread applications in various fields, including optoelectronic devices. Owing to the limitations of rare-earth elements and heavy toxic effects of chalcogenides and perovskite quantum dots on the environment and biological systems, researchers have started focusing on CDs/CPDs to overcome the drawbacks of conventional phosphor materials. In this talk, we introduce some of our recently developed light-emitting devices combining metal-free carbogenic phosphors and DBR based microcavity as well as microbeads for controlling the sharp resonant emission and chromaticity via wavelength-selective photoluminescence as well as lasing and infrared emission. By adopting Fabri-Perot structure with two dielectric multilayer-photonic mirrors, we could realize light amplification in the blue wavelength region. We could also observe whispering gallery mode from the CPDs in the visible to the red and finally in the near infrared region. These proposed devices in this study will open a new avenue for potential applications in chromaticitytunable white light emitters, lasers5, spectroscopic authentication, and single-microparticle-based chemical/bio sensing.
