Unprecedented Fluorophore Photostability Enabled by Low‐Loss Organic Hyperbolic Materials

Abstract

The dynamics of photons in fluorescent molecules plays a key role in fluorescence imaging, optical sensing, organic photovoltaics, and displays. Photobleaching is an irreversible photodegradation process of fluorophores, representing a fundamental limitation in relevant optical applications. Chemical reagents are used to suppress the photobleaching rate but with exceptionally high specificity for each type of fluorophore. Here, using organic hyperbolic materials (OHMs), an optical platform to achieve unprecedented fluorophore photostability without any chemical specificity is demonstrated. A more than 500‐fold lengthening of the photobleaching lifetime and a 230‐fold increase in the total emitted photon counts are observed simultaneously. These exceptional improvements solely come from the low‐loss hyperbolic dispersion of OHM films and the large resultant Purcell effect in the visible spectral range. The demonstrated OHM platform may open up a new paradigm in nanophotonics and organic plasmonics for super‐resolution imaging and the engineering of light–matter interactions at the nanoscale.

Organic Hyperbolic Material Assisted Illumination Nanoscopy

“…Note that during the image acquisitions, almost negligible photobleaching was observed because of the significantly reduced photobleaching rates by hyperbolic optical modes supported by the OHM due to the large resultant Purcell effect. [ 27 ]…”

“…With periodicity at 1.6 nm, hyperbolic dispersion of the developed OHM film supports remarkably high‐ k optical modes in the visible frequency. Comparing to inorganic counterparts, the OHMs not only provide better deep subwavelength‐scale illuminating field confinement in visible spectral range, but also offer many advantages such as extremely enhanced photostability of fluorophores near the OHM, [ 27 ] easy fabrication process, and excellent biocompatibility [ 28 , 29 ] for bioimaging applications.…”

Hyperbolic metamaterials: fusing artificial structures to natural 2D materials

“…The development of hyperbolic media that will lead to the improvement of influential optical devices is more extensive than the contents of this review. For example, photostability, low-loss organic HMMs and super-resolution imaging platform using HMMs are being actively investigated [90,[234][235][236][237][238]. The propagation of light in HMMs can be applied to various optical components for collimation [70,239], splitters [240][241][242][243], airy beams [244,245], and even with absorption and scattering for sensing and cloaking [246].…”

Next-Generation Imaging Techniques: Functional and Miniaturized Optical Lenses Based on Metamaterials and Metasurfaces

“…Thus, recently reported results are promising in that they have reduced the complexity of sophisticated optical systems and have opened up a wide range of possible applications. Development of hyperlenses has shown the possibility of producing low-cost, large-area devices by large-scale fabrication [32], but research is pursuing innovation by use of various materials to widen the operating wavelength range and increase the efficiency; examples include investigation of organic hyperbolic metamaterials that have low loss or photostability [92]. The use of ultra-small, ultra-high-resolution functional materials has the potential to develop portable devices that can measure various samples with increased efficiency and that can diagnose diseases and identify viruses.…”