Two Hundred Nanometer\nThin Multifocal Graphene Oxide\nMetalens for Varying Magnification Broadband Imaging

Conventional microscopes, which rely on multiple objective\nlenses\nfor varying magnifications, are bulky, complex, and costly, making\nthem difficult to integrate into compact devices. They require frequent\nmanual adjustments, complicating the imaging process and increasing\nmaintenance burdens. This paper explores the potential of single ultrathin\ngraphene metalens to address this issue. We propose and demonstrate\na 200 nm thin multiaxial focus graphene metalens with high-quality\nfocusing, designed using spatial multiplexing and fabricated by one-step\nlaser nanoprinting. A five-focal graphene metalens has been created,\nachieving clear imaging with varying magnifications across a broadband\ncovering the entire visible wavelength. The graphene metalens has\nsignificantly reduced the size of the imaging system by orders of\nmagnitude and holds profound potential for facilitating the integration\nand miniaturization of optical microscopic systems.