The novel properties of metamaterial devices are mainly from their designed nanostructures. The size, geometry, shape, orientation, and specific arrangement can provide new and useful functions beyond conventional materials' capability. The fabrication process of meta-device could be compatible with the semiconductor microelectronics mass production. The advantages of meta-devices are lightweight and small size with the possibility of high efficiency, better performance, broad bandwidth, and lower energy consumption in the system level. For example, meta-lens was listed as one of the top 10 emerging technologies in the World Economic Forum. The intrinsic advantage is spherical aberration-free. The basic principle, design, fabrication, and applications of the novel optical meta-devices are addressed in this talk. The achromatic meta-lenses for optical imaging and light-field sensing will be shown. Meta-lenses used in water or drone in the air, quantum optics, and bio-medical applications are demonstrated. The prospects of the demanded meta-devices for the metaverse will be discussed. The meta-devices open up an avenue for future novel applications in micro-robotic vision, unmanned-vehicle sensing, virtual and augmented reality, miniature personal security systems, biomedical, healthcare, and quantum information technologies, etc.

Modern technologies such as scanning tunneling microscopy (STM) and atomic force microscopy (AFM) heavily rely on one’s ability to control and maintain the gap between two objects, often with a picometer precision. These quantum technologies have their applications often limited to imaging or to single objects manipulations because of the small device footprints of the point-like gap architectures. We refer to the AFM and STM technologies and the scanning probe microscopies (SPM) in general ‘0-dimensional gaptronics’. For photonic applications encompassing the microwave and terahertz regime, we need to vastly increase the effective area of gap control, to truly a macroscopic scale (Fig. 1). The wafer-length gaps are tunable from zero to 1000 nm (25% strain), with the ‘zero nanometer’ essentially being frequency dependent. Closing the gap over the uniform length of nanotrenches traversing tunneling, quantized conductance and semi-classical regimes produces an extinction better than 10,000 repeatable over 10,000 times in real time for incident terahertz and microwave electromagnetic waves. Our results have far-reaching implications in bridging the gap between the quantum world and the macroscopic one and we anticipate wide ranging applications in wireless communications, molecular sensing, quantum measurements, electrochemistry and photocatalysis.

Scanning probe microscopy (SPM) is arguably the most versatile and powerful 3rd generation microscopy technology for studying samples at the nanoscale. It is versatile because an SPM can not only image in three-dimensional topography but also provides various types of surface measurements to the needs of scientists and engineers. One of the SPM technologies is Scanning Near Field Optical Microscopy. Among the various developed SPMs, the Atomic Force Microscope (AFM) is the most widely used. The ability to measure forces, as indicated by the deflection of the AFM cantilever, has put it into prominence in surveying various properties of materials. Over the past three decades, AFM has evolved into an ideal methodology for non-destructive sample scanning with longer tip life, higher accuracy, repeatability, and automation. Along the way, various SPM techniques were developed to study the structures and functions of the target sample. In addition to the recent advances in SPM technology, it further expands the SPM application by combining it with other metrological technologies. Through this presentation, I will briefly introduce the 40 years of SPM technology development, contributions to real-life applications, and prospects.

The modification of images to support the extraction of information such as edge detection, identifying specific objects, or enhancing contrast of images of weakly absorbing objects is ubiquitous in contemporary spatial information management. Applications lie in areas as diverse as autonomous vehicles, remote sensing for agriculture, medicine, and biological imaging. Computational approaches are widely used, but the massive increase in the quantity of data being is accompanied by corresponding increases in energy consumption and processing time. Furthermore, and a particular focus of this presentation, typical imaging sensors are insensitive to phase information carried by an optical field which arises from transmission through transparent objects such as live cells. Although sophisticated computational methods such as ptychography can recover phase data from intensity measurements, these techniques can also be slow and data intensive. Well-established all-optical methods for real-time image processing exist but typically require the use of comparatively bulky optical components creating a barrier to their incorporation into next-generation miniaturized optical systems. Consequently, there has been a rapidly growing interest in the development of compact devices utilizing nanophotonics to manipulate images and extract essential information. This presentation will discuss recent progress in all-optical image processing using metasurfaces and emerging applications.