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  1. Confocal microscopes and two-photon microscopes are powerful tools for early cancer diagnosis because of their high-resolution 3D imaging capability, but applying them for clinical use in internal organs is hindered by the lack of axially tunable lens modules with small size, high image quality and large tuning range. This paper reports a compact MEMS lens scanner that has the potential to overcome this limitation. The MEMS lens scanner consists of a MEMS microstage and a microlens. The MEMS microstage is based on a unique serpentine inverted-series-connected (ISC) electrothermal bimorph actuator design. The microlens is an aspheric glass lens to ensure optical quality. The MEMS microstage has been fabricated and the lens scanner has been successfully assembled. The entire lens scanner is circular with an outer diameter of 4.4 mm and a clear optical aperture of 1.8 mm. Experiments show that the tunable range reaches over 200 µm at only 10.5 V and the stiffness of the microstage is 6.2 N/m. Depth scan imaging by the MEMS lens scanner has also been demonstrated with a 2.2 µm resolution, only limited by the available resolution target.

  2. Magnonics, which employs spin-waves to transmit and process information, is a promising venue for low-power data processing. One of the major challenges is the local control of the spin-wave propagation path. Here, we introduce the concept of writable magnonics by taking advantage of the highly flexible reconfigurability and rewritability of artificial spin ice systems. Using micromagnetic simulations, we show that globally switchable spin-wave propagation and locally writable spin-wave nanochannels can be realized in a ferromagnetic thin film underlying an artificial pinwheel spin ice. The rewritable magnonics enabled by reconfigurable spin wave nanochannels provides a unique setting to design programmable magnonic circuits and logic devices for ultra-low power applications.