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Background: There is a critical need for a rapid and sensitive pathogen detection method for septic patients. This study aimed to investigate the diagnostic efficacy of Digital droplet polymerase chain reaction (ddPCR) in identifying pathogens among suspected septic patients. Methods: We conducted a prospective pilot diagnostic study to clinically validate the multiplex ddPCR panel in diagnosing suspected septic patients. A total of 100 sepsis episodes of 89 patients were included in the study. Results: In comparison to blood culture, the ddPCR panel exhibited an overall sensitivity of 75.0% and a specificity of 69.7%, ddPCR yielded an additional detection rate of 17.0% for sepsis cases overall, with a turnaround time of 2.5 h. The sensitivity of ddPCR in the empirical antibiotic treatment and the non-empirical antibiotic treatment group were 78.6% versus 80.0% (p > 0.05). Antimicrobial resistance genes were identified in a total of 13 samples. Whenever ddPCR detected the genes beta-lactamase-Klebsiella pneumoniae carbapenemase (blaKPC) or beta-lactamase-New Delhi metallo (blaNDM), these findings corresponded to the cultivation of carbapenem-resistant gram-negative bacteria. Dynamic ddPCR monitoring revealed a consistent alignment between the quantitative ddPCR results and the trends observed in C-reactive protein and procalcitonin levels. Conclusions: Compared to blood culture, ddPCR exhibited higher sensitivity for pathogen diagnosis in suspected septic patients, and it provided pathogen and drug resistance information in a shorter time. The quantitative results of ddPCR generally aligned with the trends seen in C-reactive protein and procalcitonin levels, indicating that ddPCR can serve as a dynamic monitoring tool for pathogen load in septic patients. [ABSTRACT FROM AUTHOR]

Modulation of light underpins a central part of modern optoelectronics. Conventional optical modulators based on refractive‐index and absorption variation in the presence of an electric field serve as the workhorse for diverse photonic technologies. However, these approaches based on electro‐refraction or electro‐absorption effect impose limitations on frequency converting and signal amplification. Lanthanide‐activated phosphors offer a promising platform for nonlinear frequency conversion with an abundant spectrum. Here, we propose a novel approach to achieve frequency conversion and digital modulation of light signal by coupling lanthanide luminescence with an electrically responsive ferroelectric host. The technological benefits of such paradigm‐shifting solution are highlighted by demonstrating a quasi‐continuous and enhancement of the lanthanide luminescence. The ability to locally manipulate light emission can convert digital information signals into visible waveforms, and visualize electrical logic and arithmetic operations. The proof‐of‐concept device exhibits perspectives for developing light‐compatible logic functions. These results pave the way to design more controllable lanthanide photonics with desired opto‐electronic coupling. [ABSTRACT FROM AUTHOR]

In silicon photonics, BaTiO3 (BTO) emerges as a promising electro‐optic (EO) integrated material due to its excellent EO modulation capabilities. Nevertheless, the EO response of multi‐domain BTO thin films tends to be lower than that of bulk materials. BTO thin films are fabricated with strong EO responses utilizing the pulsed laser deposition technique. Considering the importance of the SrTiO3 (STO) buffer layer, a series of epitaxial BTO thin films are deposited on STO substrates with engineered domain alignment. Given the contribution of domain variants in BTO thin films to their EO response, specific electrode patterns are designed to enhance their performance. An effective Pockels coefficient of 286 pm V−1 is determined for the BTO thin film via the transmission geometry method, which surpasses recent reports. Through domain engineering in the BTO thin film, the remarkable enhancement in the EO response arising from in‐plane polarization (a‐axis) characteristics is confirmed. Simultaneously, utilizing the Second Harmonic Generation (SHG) optical probe, deep exploration into the domain dynamics within BTO thin films is conducted. These findings provide insights into the contribution of domain variants to the EO response and shed light on further developing silicon‐based heterogeneously integrated devices. [ABSTRACT FROM AUTHOR]

Swift heavy Ta ions with an ultra-high energy of 2896 MeV are utilized for irradiation of β-Ga2O3 photodetectors. Noteworthy variations in device performance under different wavelengths are observed. Under 254 nm light illumination, the photocurrent of the devices exhibit degradation at low ion fluences but gradually recover and even surpass the performance of non-irradiated devices at the irradiation fluence of 1 × 1010 cm−2. Conversely, under 365 nm light illumination, photocurrent increases at low fluence but slightly decreases at the same high fluence of 1 × 1010 cm−2. Cathodoluminescence spectra and first-principles calculations elucidate the mechanism underlying the evolution of device performance with irradiation fluence. At low irradiation fluence, the introduction of point defects such as oxygen vacancies and gallium vacancies leads to an expansion of the bandgap, resulting in a decline in photocurrent under 254 nm light illumination. Additionally, deep defect levels are generated by these point defects, promoting an enhancement of photocurrent under 365 nm light illumination. Higher fluences transform these point defects into complex defects such as Ga–O pair vacancies, resulting in a reduction in the bandgap. Consequently, an increase in photocurrent is observed for devices illuminated with 254 nm light. However, at high irradiation fluences, charge recombination induced by the presence of deep defect levels becomes more significant, leading to a decrease in photocurrent when exposed to 365 nm light. No matter what, at 1 × 1010 cm−2 fluence, β-Ga2O3 photodetectors still maintain excellent performance, implying their strong radiation resistance and immense potential for application in space environments. [ABSTRACT FROM AUTHOR]

Gallium oxide (Ga2O3) is an emerging wide bandgap semiconductor promising a wide range of important applications. However, mass production of high-quality crystalline Ga2O3 still suffers from limitations associated with poor reproducibility and low efficiency. Low-temperature-grown amorphous Ga2O3 demonstrates comparable performance with its crystalline counterparts. Lanthanide Er3+-doped Ga2O3 (Ga2O3: Er) possesses great potential for developing light-emitting devices, photodetectors, solid-state lasers, and optical waveguides. The host circumstance can exert a crystal field around the lanthanide dopants and strongly influence their photoluminescence properties. Here, we present a systematical study of the impact of amorphous-to-crystalline transition on the upconversion photoluminescence in Ga2O3: Er thin films. Through controlling the growth temperature of Ga2O3: Er films, the upconversion luminescence of crystalline Ga2O3: Er thin film is strongly enhanced over 100 times that of the amorphous Ga2O3: Er thin film. Moreover, the variation of photoluminescence reflects the amorphous-to-crystalline transformation of the Ga2O3: Er thin films. These results will aid further designs of favorable optoelectronic devices integrated with lanthanide-doped Ga2O3 thin films. [ABSTRACT FROM AUTHOR]

Light-emitting diodes (LEDs) combined with near-infrared (NIR) phosphors are rapidly becoming important light sources for food safety, anti-counterfeiting and biological imaging due to non-destructive and non-toxic advantages. Single-phase materials with multi-mode luminescence under different stimuli are crucial for the development and applications of smart NIR phosphors. Here, we have developed multifunctional Cr3+ activated MgGa2O4 (MGO:Cr3+) phosphors with simultaneous photoluminescence and mechanoluminescence for NIR sensing. Under 470 nm excitation, the phosphors can produce emission bands from 650 to 850 nm. Meanwhile, the flexible devices based on phosphors can exhibit strong emissions in response to mechanical deformation, such as shock and friction. In addition, optical manometers based on luminescence from phosphors can achieve pressure sensing from 7 to 64 KPa. More intriguingly, we combined the MGO:Cr3+ phosphor with a blue LED chip to fabricate an NIR phosphor-converted LED for anti-counterfeiting and biological tissue penetration. Our results suggest that the multifunctional NIR phosphors with simultaneous photoluminescence and mechanoluminescence have potential applications in various sensing devices. [ABSTRACT FROM AUTHOR]

Silicon, renowned for its applications in electronic circuits, also offers significant advantages in the realm of integrated optics. While silicon does have inherent limitations in fabricating active devices, these challenges can be overcome through heterogeneous integration with other materials. Ferroelectric materials like lithium niobate (LN) and barium titanate (BTO) exhibit exceptional electrical and nonlinear optical properties, making them ideal candidates for integrated silicon photonics. Over the past few decades, the LN platform has made substantial progress, surmounting obstacles such as manufacturing difficulties, high waveguide losses, and low modulation bandwidth caused by wide electrode spacing. Consequently, LN-based devices have found widespread application in various fields. With the advent of high-quality, large-size LN on insulator wafers, LN photonics has become a burgeoning research area. At the same time, the ferroelectric material BTO, with its tremendous electro-optic response, shows promise for the next generation of integrated photonics. Recent studies have highlighted the remarkable performance of BTO-based modulators, which offer smaller device sizes compared to LN by achieving lower half-wave voltages. This comprehensive review presents various fabrication methods for integrating LN and BTO thin films on silicon, focusing on recent advancements. We discuss their electro-optic responses and provide an overview of the diverse applications enabled by these platforms. Finally, we summarize the current state of integrated LN and BTO photonics research and offer insights into future directions. [ABSTRACT FROM AUTHOR]

With the development of Raman spectroscopy and the expansion of its application domains, conventional methods for spectral data analysis have manifested many limitations. Exploring new approaches to facilitate Raman spectroscopy and analysis has become an area of intensifying focus for research. It has been demonstrated that machine learning techniques can more efficiently extract valuable information from spectral data, creating unprecedented opportunities for analytical science. This paper outlines traditional and more recently developed statistical methods that are commonly used in machine learning (ML) and ML‐algorithms for different Raman spectroscopy‐based classification and recognition applications. The methods include Principal Component Analysis, K‐Nearest Neighbor, Random Forest, and Support Vector Machine, as well as neural network‐based deep learning algorithms such as Artificial Neural Networks, Convolutional Neural Networks, etc. The bulk of the review is dedicated to the research advances in machine learning applied to Raman spectroscopy from several fields, including material science, biomedical applications, food science, and others, which reached impressive levels of analytical accuracy. The combination of Raman spectroscopy and machine learning offers unprecedented opportunities to achieve high throughput and fast identification in many of these application fields. The limitations of current studies are also discussed and perspectives on future research are provided. [ABSTRACT FROM AUTHOR]

Ga2O3 has generated considerable interest as a wide bandgap semiconductor and is used for solar-blind deep ultraviolet photodetectors. Additionally, graphene serving as a transparent electrode material can improve device performance. However, due to defects at the contact interface between graphene and Ga2O3, existing devices based on graphene/Ga2O3 are liable to elevated dark currents. In this work, we constructed a graphene/β-Ga2O3/Ag asymmetric Schottky junction photodetector, which addresses this issue. Taking advantage of the asymmetric structure design to suppress dark current and the transparent graphene electrode increasing the carrier collection efficiency, the device achieved an outstanding responsivity of 44.09 A W−1, a high detectivity of 5.84 × 1012 Jones, a remarkable external quantum efficiency of 2.15 × 104%, and a fast response time of 99.60 ms/27.74 ms. More importantly, owing to reverse bias voltage on the high barrier side, it possesses a low dark current of 12.09 pA with a light-to-dark ratio of up to 104. All in all, the graphene/β-Ga2O3/Ag asymmetric Schottky junction photodetector has considerable potential as a deep ultraviolet detector. [ABSTRACT FROM AUTHOR]

Near-infrared luminescence phosphors are key material basis to potential applications for light sources and optoelectronic devices. In particular, it is vital to tune the luminescent properties of these phosphors in a flexible and controllable manner. Here, we demonstrate that a flexural strain originated from bending can be used to modulate the photoluminescence of freestanding Ni2+ doped SrTiO3 membranes. The bent membranes show remarkable red-shift emissions, arising from the variations of the symmetry of host materials and the local crystal fields around the Ni2+ ions. In addition, the phosphor films show a reversible and stable wavelength modulation with remarkable anti-fatigue characteristics after 104 bending cycles. These results provide a potential routine to develop flexible strain-tunable devices for applications in optical amplifiers and other optoelectronics. [ABSTRACT FROM AUTHOR]