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Plasmon-induced transparency (PIT) metasurfaces have emerged as a promising platform for applications in ultrasensitive detection and slow-light devices. The active control of PIT metasurfaces is particularly crucial for advancing these applications. In this study, we integrate the phase change material Ge2Sb2Te5 (GST) into the structural design of a polarization-independent metasurface, enabling the experimental realization of ultra-large depth modulation of PIT peaks. This was achieved through direct thermal activation of the sample and laser-induced multilevel nonvolatile modulation, with a modulation range extending from 0% to 35.2%. The underlying mechanism for this significant modulation depth is attributed to the suppression of magnetic resonance by the GST phase transition, which is elucidated through analyses of multipolar scattering power, electric field distribution, and magnetic field distribution. The proposed terahertz metasurface presents a pathway for the development of optical switches and slow-light devices, with potential applications in advanced photonic systems. [ABSTRACT FROM AUTHOR]

Perfect vector vortex beams play a very important role in understanding complex structured beams due to their vortex nature and nonuniform polarization profiles. However, the generation of these beams suffers from a limited number of topological charges, bulky optical setup, lack of color information, and limited control along the light propagation direction. To tackle these fundamental and technical challenges, a metasurface approach to generating multiple grafted perfect vector vortex beams (GPVVBs) along the light propagation direction. GPVVBs with different colors are observed by changing the observation plane is proposed. Their polarization profiles are indirectly confirmed through the unique features in the modulated intensity profiles with an analyzer. Furthermore, the dynamic control of these beams is realized by continuously changing the incident polarization. Simultaneous control of color and topological charges in GPVVBs along the longitudinal direction provides more degrees of freedom for carrying information and has the potential to impact quantum science, singular optics, and optical communications. [ABSTRACT FROM AUTHOR]

Polarization state generation plays an important role in optics and are applied in many fields. Multispectral polarization manipulation can increase information capacity. To meet the requirement of miniaturization and integration, it is desirable to generate multispectral polarization states with a compact optical device. a metasurface device is proposed and experimentally demonstrated, which can simultaneously realize wavelength separation and polarization generation. A geometric metasurface is used to realize the phase and wavelength multiplexing. Six polarization states with different wavelengths are generated. Customized polarization states with predesigned wavelength information can add extra degrees of freedom for carrying information, opening a new window for portable polarization optics where low‐cost and miniaturized systems are in high demand. [ABSTRACT FROM AUTHOR]

Rationale: Among mechanically ventilated critically ill adults, the PILOT (Pragmatic Investigation of Optimal Oxygen Targets) trial demonstrated no difference in ventilator-free days among lower, intermediate, and higher oxygen-saturation targets. The effects on long-term cognition and related outcomes are unknown. Objectives: To compare the effects of lower (90% [range, 88–92%]), intermediate (94% [range, 92–96%]), and higher (98% [range, 96–100%]) oxygen-saturation targets on long-term outcomes. Methods: Twelve months after enrollment in the PILOT trial, blinded neuropsychological raters conducted assessments of cognition, disability, employment status, and quality of life. The primary outcome was global cognition as measured using the Telephone Montreal Cognitive Assessment. In a subset of patients, an expanded neuropsychological battery measured executive function, attention, immediate and delayed memory, verbal fluency, and abstraction. Measurements and Main Results: A total of 501 patients completed follow-up, including 142 in the lower, 186 in the intermediate, and 173 in the higher oxygen target groups. Median (interquartile range) peripheral oxygen saturation values in the lower, intermediate, and higher target groups were 94% (91–96%), 95% (93–97%), and 97% (95–99%), respectively. Telephone Montreal Cognitive Assessment score did not differ between lower and intermediate (adjusted odds ratio [OR], 1.36 [95% confidence interval (CI), 0.92–2.00]), intermediate and higher (adjusted OR, 0.90 [95% CI, 0.62–1.29]), or higher and lower (adjusted OR, 1.22 [95% CI, 0.83–1.79]) target groups. There was also no difference in individual cognitive domains, disability, employment, or quality of life. Conclusions: Among mechanically ventilated critically ill adults who completed follow-up at 12 months, oxygen-saturation targets were not associated with cognition or related outcomes. [ABSTRACT FROM AUTHOR]

As an attractive metal‐free conjugated polymer, graphitic carbon nitride (g‐C3N4) has attracted extensive attention in the field of solar energy conversion and storage as a visible light responsive hydrogen evolution. However, the photocatalytic efficiency of g‐C3N4 still has great room for improvement. Herein, a highly efficient visible‐light‐driven okra‐like tubular g‐C3N4photocatalyst (TCNMCA‐PImM) was synthesized via pyrolysis of a poly‐(imidazolium‐methylene) chloride (PImM)‐mediated molecular assembly prepared by a hydrothermal process of a solution containing PImM, melamine, and KOH, in which PImM acts as an electronic structure regulator owing to its strong hydrogen bond, π‐π interaction, and van der Waals force. On the basis of maintaining tri‐s‐triazine structure, the increase of graphitic N promotes the separation and transfer efficiency of photogenerated electrons and holes through the electron structure adjustment. The photocatalyst displays the notably promoted photocatalytic performance for H2 generation under visible‐light illumination. The optimized photocatalyst shows 1902 μmol h−1 g−1 of hydrogen evolution rate, which is 25.7 times higher than that of bulk g‐C3N4. The developed polymeric carbon nitride with unique geometric structure and electronic properties can be extended to other applications like CO2 capture for carbon neutralization strategy. [ABSTRACT FROM AUTHOR]