Shiqi Luo

Projects: (i) Fabricating Fresnel Zone Plate with Extended Depth of Focus Through GST Photothermal Lithography: ● Proposed a novel method for extending Fresnel zone plate (FZP) depth of focus (DOF) by segmenting it into sub-areas with tunable focal lengths and spatial arrangements. ● Simulated the segmented FZP design in Python and achieved a 15.7× increase in DOF through parameter optimization. ● Fabricated the optimized FZP on 50 nm GST thin films using a two-step process of laser direct writing and wet etching. ● Verified <5% average ring width deviation through SEM characterization. ● Built an FZP testing platform and demonstrated a 13.6× experimental DOF extension. (ii) Direct laser writing lithography of photoinsensitive durable GST thin films with near 100% yield: ● Operate direct laser writing lithography system, achieving precise patterning on the GST thin film. ● Apply wet etch and dry etch for subsequent processing of patterned samples. ● Ensure pattern quality via optical microscopy, AFM, and SEM, resulting in consistent and reproducible patterning. ● Achieve a 300 nm feature size and nearly 100% yield, demonstrating high resolution and advanced fabrication capabilities. (iii) Maskless Lithography System based on Digital Micromirror Device (DMD) and Metalens: ● Design a 532 nm metalens in FDTD with Si3N4 nanopillars and an SiO2 substrate, achieving a 385 nm FWHM focal spot. ● Fabricate the designed metalens in class 100 cleanroom using PECVD, EBL, ICP-RIE, etc. ● Develop a DMD/metalens-based lithography system, improving efficiency by simultaneous direct writing of 400 laser points. ● Develop a LabVIEW gap-measurement system, minimizing errors in the fabrication process. ● Coordinate synchronization of optical components by using LabVIEW, achieving precise arbitrary patterning.

● Performed testing on 84×84-port Optical Circuit Switches (OCS) using Python and LabVIEW, establishing testing standards at both the module level and chassis level. ● Evaluated seven key optical parameters: insertion loss (IL), polarization dependent loss (PDL), power-off IL, switching time, dynamic/cumulative crosstalk (XT), return loss (RL), and wavelength dependent loss (WDL). ● Developed 11 OCS control protocol scripts in Python, enabling port mapping, voltage calibration, and configuration management; supported dynamic port reconfiguration and precise voltage tuning of liquid crystal (LC) cells. ● Built a Python-based automated testing framework for data acquisition, analysis, and optimization of OCS performance.

Project: Image Edge Detection based on Optical Metasurface: ● Designed a 2 mm-diameter TiO₂ metasurface for image edge detection, with achromatic optimization via FDTD. ● Exploited spin–orbit interaction of light to modulate geometric phase, enabling polarization-independent edge detection. ● Integrated with MATLAB algorithms to extract isotropic edges of biological cells for imaging applications.