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As one of the most widely used infrared (IR) detectors, a mercury cadmium telluride (MCT) detector usually requires liquid nitrogen refrigeration to suppress thermally activated noise mechanisms that are inherent to its narrow bandgap, which limits its practical applications. Therefore, it is essential to develop strategies to suppress dark current with reduced cooling demand. In this work, a surface plasmon resonance (SPR) enhanced MCT microcavity was proposed to intensify optical absorption across a broadband while diminishing the thickness of the MCT layer to reduce intrinsic dark current proportional to the volume of the absorber. The microcavity is formed by sandwiching the MCT layer between a top well-designed hybrid golden-cross antenna array and a bottom golden reflector. The microcavity is employed to trap the incident light to amplify the absorption, and the golden-cross antenna array is introduced to not only significantly enhance the incident light field through the SPR effect but also to broaden the microcavity resonant mode. Numerical calculation indicated that an absorptance exceeding 95.3% can be attained at 3.4 μm with the full width at half maxima (FWHM) extending beyond 1.38 μm, which almost covers the absorption band of MCT in mid-wavelength IR (MWIR), all while the MCT layer is only 530 nm. Moreover, the prototype device unit was fabricated and tested. Measured peak absorption reached 98.7% @ 3.6 μm and FWHM was as broad as 1.12 μm. These results demonstrate that the high and wideband absorption in an ultrathin MCT layer is achieved based on the synergistic effects of SPR and microcavity resonance. [ABSTRACT FROM AUTHOR]

As large‐area and optically transparent photon harvesting devices, luminescent solar concentrators (LSCs) are promising candidates for building‐integrated photovoltaics owing to their high transmittance and resistance to shadowing effects existing in solar cells. Up to now, there are still many challenges in the practical application of LSCs: 1) Reabsorption loss is inevitable during photoluminescence transmission due to indirect illumination of solar cells in LSC system. 2) Satisfactory energy harvesting cannot be achieved in rainy conditions due to the substantial attenuation of the incident light intensity. 3) Evaporation residue on the surface of LSCs leads to device performance degradation. Pioneering researches and feasible strategies for reabsorption loss suppression, energy harvesting in rainy days as well as self‐cleaning property are still lacking demonstration. In this work, reabsorption loss is suppressed based on advanced structural LSCs with universally applicable optical spacer layer. Then the integrated LSCs with droplet‐based electricity generator (DEG) are proposed for the first time. Such DEG‐LSCs not only realize synergistic harvesting of solar and raindrop energy, but also possess self‐cleaning properties. Finally, a self‐powered temperature and humidity sensing system is designed and demonstrated to provide feasible ideas for the practical application of DEG‐LSCs in self‐powered intelligent buildings. [ABSTRACT FROM AUTHOR]

To keep pace with the demands of modern photonic integration technology, the electro-optic modulator should feature multi-parameter tunable components and a compact size. Here, we propose a hybrid structure that can modulate the multi-parameters of surface plasmon polaritons (SPPs) simultaneously with a compact size by controlling the electron concentration of indium tin oxide (ITO) in the near-infrared spectrum. The length, width and height of the device are only 15 μm, 5 μm and 9 μm, respectively. The numerical results show that when the electron concentration in ITO changes from 7.5 × 1026 m−3 to 9.5 × 1026 m−3, the variation in amplitude, wavelength and phase are 49%, 300 nm and 347°, respectively. The demonstrated structure paves a new way for multi-parameter modulation and the realization of ultracompact modulators. [ABSTRACT FROM AUTHOR]

The random laser from sheared dye-doped polymer-dispersed liquid crystal (DDPDLC) is investigated. As the emission intensity weakens, the threshold of random laser from DDPDLC increases from 2.0 mJ/pulse to 4.0 mJ/pulse, and the degree of polarization (DOP) increases from 0.1 to 0.78, obviously when the shear distance increases from 0 mm to 4 mm. As the liquid crystal droplets are gradually oriented in the shear direction caused by alignment direction of polymer chain and anisotropy of droplet shape, the scattering intensity perpendicular to the shear direction gradually decreases and that parallel to the shear direction gradually increases. The anisotropic absorption of the laser dye also plays a certain role as the shear distance is 0 mm. The controllable intensity and polarization degree of random laser have a huge potential for sensing applications.

The solar‐only response nature limits the luminescent solar concentrators (LSCs) to solar harvesting rather than responding to other stimuli, which restricts the role of LSCs to energy supply in self‐powered internet of things (IoT) systems, and the application potential of LSCs in self‐powered devices has been seriously overlooked. In this work, LSCs with photovoltaic and piezoelectric features are proposed for the first time, extending the application scenario of LSCs to self‐powered sensors with pressure responsiveness. The luminescent layer of perovskite‐polymer composite film is prepared via in situ blade coating with the piezoelectric polymer matrix of poly(vinylidenefluoride‐trifluoroethylene) (P(VDF‐TrFE)). P(VDF‐TrFE) possesses stronger DMF adsorption capacity and higher electroactive phase content than a conventional piezoelectric matrix of poly(vinylidene fluoride) (PVDF), which not only reduces the residual‐solvent‐induced defects in perovskite luminophores, but also brings a sensitive pressure response to LSCs. The dual‐functional LSCs achieve a power conversion efficiency of 1.01% and a output piezoelectric voltage of 0.95 V can be obtained even at a low pressure of 0.16 kPa. A self‐powered speed measurement system is demonstrated, and the actual speed measurement is carried out. Such dual‐functional LSCs show great potential in self‐powered electrical devices, which can be applied to low‐energy‐consumption IoT systems and other commercial smart home products. [ABSTRACT FROM AUTHOR]

With the growing safety concerns related to the toxicity of lead halide perovskites, there is an urgent need for novel lead-free alternatives. Recently, copper halide perovskites (CHPs) have attracted much attention for their outstanding stability and high luminescence efficiency. Although the related literature was developed over a brief period of only a few years, progress to date includes the synthesis of CHPs in different forms and dimensions, characterized by different peak positions and dopant manipulations, for use in applications spanning light emission, energy harvesting, light detection, anti-counterfeiting, memory devices, and neurocomputing, among others. The present paper aims to synthesize the existing body of literature by providing a systematic literature review on this subject. In this review, we discuss recent progress in the aforementioned areas, and identify critical challenges that must be addressed to further the development and application of CHPs for real-world application and to facilitate the commercialization of CHPs. [ABSTRACT FROM AUTHOR]

This paper introduces a unique multiyear dataset and the monitoring capability of the PANDA automatic weather station network, which includes 11 automatic weather stations (AWSs) across the Prydz Bay–Amery Ice Shelf–Dome A area from the coast to the summit of the East Antarctic Ice Sheet. The ∼ 1460 km transect from Zhongshan to Panda S follows roughly along ∼ 77 ∘ E longitude and covers all geographic units of East Antarctica. Initial inland observations, near the coast, started in the 1996/97 austral summer. All AWSs in this network measure air temperature, relative humidity, air pressure, wind speed and wind direction at 1 h intervals, and some of them can also measure firn temperature and shortwave/longwave radiation. Data are relayed in near real time via the Argos system. The data quality is generally very reliable, and the data have been used widely. In this paper, we firstly present a detailed overview of the AWSs, including the sensor characteristics, installation procedure, data quality control protocol and the basic analysis of each variable. We then give an example of a short-term atmospheric event that shows the monitoring capacity of the PANDA AWS network. This dataset, which is publicly available, is planned to be updated on a near-real-time basis and should be valuable for climate change estimation, extreme weather events diagnosis, data assimilation, weather forecasting, etc. The dataset is available at 10.11888/Atmos.tpdc.272721 (Ding et al., 2022b). [ABSTRACT FROM AUTHOR]

When light illuminates a rough metallic surface, hotspots can appear, where the light is concentrated on the nanometre scale, producing an intense electromagnetic field. This phenomenon, called the surface enhancement effect (1,2), has a broad range of potential applications, such as the detection of weak chemical signals. Hotspots are believed to be associated with localized electromagnetic modes (3,4), caused by the randomness of the surface texture. Probing the electromagnetic field of the hotspots would offer much insight towards uncovering the mechanism generating the enhancement; however, it requires a spatial resolution of 1-2 nm, which has been a long-standing challenge in optics. The resolution of an optical microscope is limited to about half the wavelength of the incident light, approximately 200-300 nm. Although current state-of-the-art techniques, including near-field scanning optical microscopy (5), electron energy-loss spectroscopy (6), cathode luminescence imaging (7) and two-photon photoemission imaging (8) have subwavelength resolution, they either introduce a non-negligible amount of perturbation, complicating interpretation of the data, or operate only in a vacuum. As a result, after more than 30 years since the discovery of the surface enhancement effect (9-11), how the local field is distributed remains unknown. Here we present a technique that uses Brownian motion of single molecules to probe the local field. It enables two-dimensional imaging of the fluorescence enhancement profile of single hotspots on the surfaces of aluminium thin films and silver nanoparticle clusters, with accuracy down to 1.2 nm. Strong fluorescence enhancements, up to 54 and 136 times respectively, are observed in those two systems. This strong enhancement indicates that the local field, which decays exponentially from the peak of a hotspot, dominates the fluorescence enhancement profile., The study of the surface enhancement effect mirrors the development of surface analysis techniques. Previous optical experiments revealed that the roughness of the surface has a critical role in determining [...]

The use of environment-friendly carbon dots (CDs) for preparing luminescent solar concentrators (LSCs) is a hot topic. Because of the low extinction coefficient of CDs and the thin film thickness, most reported LSCs fabricated by a CD-containing film on a matrix have low optical efficiency below 5%. Bulky CD-based LSCs are expected to be used as a solution because the increased thickness can compensate for the low extinction coefficient of CDs. However, the challenge is the quenched fluorescence of CDs by free radicals during polymerization. Herein, we reported free radical-resistant fluorescent solid-state CDs, which were synthesized by citric acid and N-[3-(trimethoxysilyl)-propyl]-ethylenedi-amine (DAMO). The diamine group on DAMO is important to obtain bright CDs, while siloxane groups on DAMO facilitate the formation of silica shells outside CDs. After being exposed to free radicals, as-prepared silica shell-capped CDs maintain 88.2% of the original fluorescence intensity. Furthermore, free radical-resistant CDs are used to fabricate LSCs by coupling solar cells on the side of CD–polymer composite prepared by bulk polymerization. For a typical device with the dimension of 2 cm × 2 cm × 0.5 cm, the optical efficiency is up to 9.3%, which remains constant under sunlight irradiation during the monitoring period of 65 days. [ABSTRACT FROM AUTHOR]

Room‐temperature exciton‐polariton Bose‐Einstein condensation (BEC), a phase transition to single quantum state with strong nonlinearity, provides a new strategy for coherent light sources and ultralow threshold optic switches. In this work, colloidal CdSe/CdS 2D nanoplatelets are embedded into a microcavity, and exciton‐polariton BEC is realized with an ultralow threshold of 0.5 µJ cm–2 at room temperature. The superlinear power‐dependent emission, macroscopic occupation of the ground state, strong blueshift and broadening of the emission peak, and long‐range coherence strongly confirm the realization of the polariton laser. This work suggests considerable prospects for colloidal nanoplatelets in low‐cost, high‐performance polariton devices, and coherent light sources. [ABSTRACT FROM AUTHOR]

During the fabrication of lateral‐structured photodetectors based on CH3NH3PbI3 film, antisolvents represented by toluene are usually used to accelerate the crystallization of perovskite. Using antisolvent not only leads to the formation of shrinkage holes at the bottom of the perovskite layer, but the toxicity of antisolvents would also hinder the industrial preparation of perovskite devices. An antisolvent‐free method is a possible solution to avoid these problems. Here, we report a lateral‐structured photodetector based on an antisolvent‐free method. The lateral photodetector exhibited a high responsivity of 1.75 A⋅W−1 and specific detectivity (D*) of 3.54 × 1012 Jones. In particular, the results indicated that the solvent had an influence on perovskite film morphology, crystallization, and device performance. The prepared CH3NH3PbI3 film presented needle‐like crystals and low performance with single precursor solvent N,N‐dimethylformamide (DMF). In comparison, appropriate mixing of dimethyl sulfoxide (DMSO) could improve the morphology, crystallization, and performance of the film. In addition, the solvent volume ratio of the precursor had a profound effect on the performance of the as‐prepared photodetectors. At a DMSO:DMF volume ratio of 5:5, the as‐prepared film had massive perovskite crystals and fewer defects, resulting in optimal device performance, which can be explained by Urbach energy. [ABSTRACT FROM AUTHOR]

A novel scheme of silicon-assisted surface enhanced fluorescence (SEF) is presented for SEF-based assays, where the blank signal suppression and the fluorescence signal enhancement is combined. The P-doped, (100) oriented silicon substrate is used to quench the fluorescence of Rose Bengal (RB) molecules attached to it, resulting in an effectively suppressed background signal, which is useful for a lower limit of detection (LOD). When a proper quantity of silver nanoparticles (AgNPs) is deposited on the RB-attached silicon substrate, a significant fluorescence enhancement of up to around 290 fold is obtained, which helps to improve the sensitivity in fluorescence-based assays. Besides, conventional gold nanoparticles (AuNPs) have also been demonstrated to exhibit excellent SEF effect using the presented scheme, providing improved stability and biocompatibility. The mechanism of the observed SEF effect has been investigated, and both the decreased apparent quantum yield and the silicon-induced electric field redistribution are considered to play important roles. The experimental results suggest that the presented scheme holds great potential in the SEF-based assays aiming at higher sensitivity and lower LOD. [ABSTRACT FROM AUTHOR]

Various enhanced recovery after surgery (ERAS) guidelines have been established for several kinds of adult surgeries. While the guidelines for pediatric surgeries remained to be explored. The aim of the study was to prospectively evaluate the safety and efficacy of an ERAS protocol for Hirschsprung's disease (HSCR) infants undergoing pull-through procedures. An infant-specific ERAS protocol was developed and implemented at multiple centers from June 1, 2016 to December 31, 2017. The study included 145 consecutive patients who underwent pull-through surgery for HSCR in three Children's hospitals. Patients were primarily divided into three groups based on the clinical classification and surgical methods. Group I included patients with the short segment type who received transanal endorectal pull-through (TEPT) surgery. Group II comprised of patients with the classical type and long segment type who received laparoscopic-assisted pull-through (LAPT) surgery. Group III involved patients with the long segment type (who had received ileostomy or colostomy during the neonatal period) and total colonic aganglionosis who received open pull-through (OPPT) surgery. Patients in the three groups mentioned above were randomly and equally assigned into the ERAS group and traditional (TRAD) group with random number table row randomization. The primary outcome was the length of postoperative hospital stay (LOS). Secondary outcomes of interest included white blood cell (WBC) and C-reactive protein (CRP) on postoperative day 1 (POD 1), the blood glucose at the time of anesthesia and 24 h after surgery, time to first defecation, time to regular diet, plasma markers of nutrition status on POD 5, plasma natrium on POD 5, the mean intraoperative fluid volume, time to discontinuation of intravenous infusion, incidence of postoperative complications, re-admission within 30 days, hospitalization costs, parental satisfaction, and growth from admission to 6 months after surgery. 73 and 75 patients were assigned to the TRAD and ERAS groups, respectively. There were no significant differences in demographic data. The LOS decreased from 9.5 days in the TRAD group to 7.9 days (P < 0.001) in the ERAS group. WBC count on POD 1 showed no significant difference between the two groups. CRP on POD 1 in the ERAS group was significantly lower (P < 0.001). In the ERAS group, the blood glucose was higher at anesthesia compared to the TRAD group (P < 0.001). On the contrary, the blood glucose at 24 h after surgery was significantly lower in the ERAS group (P < 0.001). Intraoperative fluid volume was lower in the EARS group (P < 0.001). ERAS could also reduce the time to first defecation (P < 0.001), discontinuation of intravenous infusion (P < 0.001) and regular diet (P < 0.001). In the ERAS group, the concentrations of prealbumin and retinol conjugated protein on POD 5 were higher than those in the TRAD group (P < 0.001, P < 0.001, respectively). The plasma natrium had no difference in the two groups on POD 5 (P > 0.05). The rate of complications (P > 0.05) and 30-day re-admission (P > 0.05) were not significantly different between the two groups. Hospitalization costs were also reduced (P < 0.001). ERAS group has a higher parental satisfaction rate, although there was no statistical difference (96% vs 89%). There was no difference in growth between the ERAS and the TRAD groups from admission to 6 months after the surgery (weight for age z score: P > 0.05, weight for length z score: P > 0.05). We also found that the shortening of LOS by the application of ERAS protocol was more obvious in the OPPT group (−2.5 ± 1.0) than that in the TEPT (−1.9 ± 1.3) and LAPT (−1.3 ± 0.4) groups. Implementation of the ERAS protocol in infants undergoing HSCR pull-through operations is safe and efficient. The ERAS protocol is worthy of recommendation. Clinical Trials.gov identifier: NCT02776176. [ABSTRACT FROM AUTHOR]