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The electron beam (e-beam) in the scanning electron microscopy (SEM) provides an appealing mobile heating source for thermal metrology with spatial resolution of ∼1 nm, but the lack of systematic quantification of the e-beam heating power limits such application development. Here, we systemically study e-beam heating in LPCVD silicon nitride (SiNx) thin-films with thickness ranging from 200 to 500 nm from both experiments and complementary Monte Carlo simulations using the CASINO software package. There is good agreement about the thickness-dependent e-beam energy absorption of thin-film between modeling predictions and experiments. Using the absorption results, we then demonstrate adapting the e-beam as a quantitative heating source by measuring the thickness-dependent thermal conductivity of SiNxthin-films, with the results validated to within 7% by a separate Joule heating experiment. The results described here will open a new avenue for using SEM e-beams as a mobile heating source for advanced nanoscale thermal metrology development.

Separators are thin microporous membranes that allow lithium-ion (Li+) transport across interfaces and through electrolyte, have a vital role in maintaining stable performance and safety of lithium batteries. However, conventional separators for rechargeable lithium batteries suffer from temperature-induced shrinkage, poor wettability, and low tensile stability, resulting in poor battery performance, short battery life, and safety hazards. To address these issues, it is crucial to address these challenges in engineering separators to meet the requirements of next-generation energy storage systems. Herein, we first discuss fundamental properties and requirements of separators for rechargeable lithium batteries. From the scientific societies, therefore, various physical and chemical modifications have been made to conventional separators, resulting in functional composite separators. This review summarizes and discusses how composite separators manage internal thermal safety in rechargeable lithium batteries, along with other benefits, including Li+conductivity, structural integrity, wettability, better rate capability, and suppression of crossover.

Orbital angular momentum (OAM) is an intrinsic property of light that has attracted increasing attention recently. In a wide range of applications that involve OAM, it is often crucial to discern the OAM states with high fidelity. In this Letter, we propose a novel method to extend the detectable range of the OAM states by adopting a multi-sector metahologram. The incident light carrying OAM would be focused by the metahologram into surface plasmon waves with separated propagation directions that are spatially sampled by multiple subwavelength detectors. Through quantizing and mapping the detector signals into a lookup table, a wide range of OAM states could be distinguished. The principle reported in this Letter may find important applications in optical communications and information processing with the OAM states.