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Manipulating the spontaneous emission rate of fluorophores is vital in creating bright incoherent illumination for optical sensing and imaging, as well as fast single-photon sources for quantum technology applications. This can be done via increasing the Purcell effect by using non-monolithic optical nanocavities; however, achieving the desired performance is challenging due to difficulties in fabrication, precise positioning, and frequency tuning of cavity-emitter coupling. Here, we demonstrate a simple approach to achieve a wavelength-dependent photoluminescence (PL) lifetime modification using monolithic organic molecular aggregates films. These single monolithic organic films are designed to have a Lorentzian dispersion, including epsilon-near-zero (ENZ) and epsilon-near-pole (ENP) spectral regions with increased and decreased photonic density of states, respectively. This dispersion leads to enhanced and depressed PL decay rates at different wavelengths. Both time-resolved photoluminescence (TRPL) and fluorescence lifetime imaging microscopy (FLIM) measurements are implemented to verify the validity of this approach. This approach offers a promising way to design dual-functional optical sources for a variety of applications, including bioimaging, sensing, data communications, and quantum photonics applications.

Single-molecule localization microscopies have gained much attention for their efficient realization of a sub-diffraction-limit imaging with the resolution down to the 10-nm range. In contrast to conventional localization microscopes, which rely on particular fluorescent probes in specific conditions, metamaterial-assisted super-resolution microscopies can be implemented with any fluorescent dye under general conditions. Here, we present a systematic study of fluorescence engineering in metamaterial assisted localization microscopy by using cyclic group metasurfaces coated with a fluorescent film. Tailored variations are clearly demonstrated in both the photoluminescence intensity and the photobleaching lifetime of fluorophores based on the spatially varied Purcell effect near the metasurfaces. The enhanced emissions and blinking dynamics of the fluorophores on these metasurfaces lead to an increased signal-to-noise ratio, and therefore give rise to a super-resolution localization image with 0.9-nm localization accuracy. Our results are not only beneficial for super-resolution localization imaging but also push the control of light–matter interactions beyond the diffraction limit.

In this study, a useful solution is proposed for assessing the safety of the ship's hull damaged by grounding in Northern Sea Route (NSR) or Arctic sea. In particular, the residual ultimate longitudinal strength of grounding damaged ship can be predicted by the grounding damage index (GDI) concept. Due to the global warming effects, the Arctic glaciers have been gradually melting, and it may bring us the new North Pole routes. However, there are uncertainties on many causes that can lead to grounding accident of the commercial vessels. In this regard, residual ultimate longitudinal strength of grounding damaged commercial ship in Arctic sea is investigated. Five (5) temperatures: room temperature (RT), −20°C, −40°C, −60°C and −80°C were adopted to consider the cold temperature effect in NSR. The Panamax class oil tanker was selected for the investigation of residual ultimate longitudinal strength of grounding damaged ship. Fifty (50) reliable damage scenarios were adopted for the evaluation of structural health by utilising Residual strength versus GDI (R-D) diagram method. From this study, a modified R-D diagram is proposed which can consider grounding damage with cold temperature effect. The obtained outcome will be useful for assessing the safety of the grounded ships in Arctic sea region by measuring the grounding damage amount and surrounding air temperature. [ABSTRACT FROM AUTHOR]