The unique three-dimensional (3D) deformations caused by nano-kirigami have enabled a new degree of freedom for reconfigurable optics. Here we demonstrate a facile nano-kirigami method that can create 3D deformed structures, which can flexibly manipulate optical properties by thermally actuated micro-/nanoscale deformations. By connecting four pairs of thermal actuators to the four sides of a gradient metasurface, large-angle beam steering (~90°) can be achieved through adjusting the temperature of the actuators. The amplitude of circular dichroism can be adjusted by thermally actuating micro-/nanoscale deformations. The 2D-to-3D transformation of curved arm structure on metallic substrate results in enhanced structural absorption, inducing an almost perfect absorption at specific wavelengths. Curved asymmetric structures can also be created by thermally actuated micro-/nanoscale deformations, which provides a novel method for cross-polarized light conversion. The proposed design with thermally actuated micro-/nanoscale deformations provides a new methodology to explore versatile reconfigurable functionalities.

Electrothermal bimorph-based scanning micromirrors typically employ widely-used silicon dioxide (SiO2) as the electrical and thermal isolation material. However, due to the brittle nature of SiO2, such micromirrors may not be able to even survive a slight collision, which greatly limits their application range. To improve the robustness of electrothermal micromirrors, a polymer material is incorporated to partially replace SiO2 as the electrical and thermal isolation material as well as the anchor material. In particular, photosensitive polyimide (PSPI) is used to simplify the fabrication process. In this work, PSPI-based electrothermal micromirrors have been designed, fabricated and tested. The PSPI-type micromirrors achieved a maximum optical scan angle of ± 19.6 ° and a maximum vertical displacement of 370 µm both at only 4 Vdc. With a mirror aperture size of 1mm × 1 mm, the PSPI-type micromirrors withstood over 200 g accelerations from either vertical or lateral directions in the impact experiment. In the drop test, the PSPI-type micromirrors survived falls to a hard floor at heights up to 21 cm. In the standard frequency sweeping vibration test, the PSPI-type micromirrors withstood 21 g and 29 g acceleration in the vertical and lateral vibration, respectively. In all these experimental tests, the PSPI-type micromirrors demonstrated at least 4 times better robustness compared to the SiO2-type micromirrors fabricated in the same batch.

Scanning MEMS mirrors can extend confocal laser microscopy into endoscopic applications, but the practical use of MEMS mirror-based confocal endomicroscopy is hindered partially by various image distortions such as barrel, fan-shaped and nonlinear distortions. In this work, the nonlinear scanning behaviors of an electrothermal MEMS mirror are analyzed and incorporated into an optical scanning model that takes all these three types of distortions into account. The model generates a 2D spatial mapping that can be applied to correct all of the image distortions in one step without a calibration board. To experimentally validate this method, a confocal laser endomicroscope employing a two-axis scanning electrothermal MEMS micromirror is designed and constructed, and confocal fluorescence images of a patterned micro-structure are obtained with the MEMS endomicroscope. The results show that the overall image distortion is reduced by at least one order of magnitude in the length direction.

Phospholipase D reacts with alcohols or water, transphosphatidylating or hydrolysing lipids such as phosphatidylcholine, generating phosphatidylalcohols or phosphatidic acid, respectively. The enzyme has been employed in many applications making use of the transphosphatidylation reaction and the enzyme’s tolerance for organic solvents in order to synthesize natural and artificial phospholipids. Yet, its catalytic properties with respect to the transphosphatidylation reaction are not well understood. Here, we introduce a novel high-throughput assay, making use of 96-well plates, that employs Fluorescamine for the detection of transphosphatidylated amino alcohols. This assay allowed to monitor the KM and VMax at different temperatures, revealing that the former will be elevated by the temperature, while the latter is increased by a combination of both temperature and alcohol acceptor concentration being elevated, suggesting that increase in temperature may open up a new binding site for the alcohol acceptor.

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