In past decades, substantial advances in terahertz (THz) science and technology have opened up a wide range of opportunities for research in physics, chemistry, material science, biology, and medicine etc. Potential applications of THz technology in biomedical analysis, linear and nonlinear spectroscopy, chemical/biological sensing, explosives detection, tomographic imaging, and nondestructive testing have thrust THz research from relative obscurity to new heights. In practice, some of the applications set higher requirements on both THz wave sources and detectors, in terms of THz pulse energy or peak electric field, bandwidth, polarization, and signal-to-noise ratio etc. Therefore, various THz sources and detectors with high peak electric field and ultra-broad bandwidth are highly desired. The requirement on THz sources and detectors with high peak field and ultra-broad bandwidth, in turn, propels the development of THz wave photonics based on gas-phase and liquid-phase plasmas.

Semiconductor quantum dots are low-dimensional nanostructures that can be obtained by epitaxial growth techniques. They are often referred to as "artificial atoms" due to their nanoscale sizes and discrete energy levels in the conduction and valence bands. The development of epitaxial quantum dots (hereinafter referred to as "quantum dots") dated back to the early 1990s, where their initially applications include temperature-insensitive semiconductor lasers. Since then, researchers have made significant improvements in almost all aspects of quantum-dot system, ranging from well-controlled epitaxial growth to a comprehensive understanding of low-dimensional semiconductor physics.

Using light to remotely and precisely manipulate objects, a concept generalized as optical manipulation, has gained strong momentum in various academic disciplines such as life sciences, quantum physics and micro-robotics, ever since its inception landmarked by the invention of optical tweezers by Arthur Ashkin, Steven Chu, and their coworkers at the Bell lab. Centering at exploiting momenta of photons and the associated optical force/torque, corresponding researches of optical manipulation have primarily dedicated to either improving the resolution of experimental apparatus to maneuver ever-smaller objects down to single atomic level, or sculpturing the wavefront of light beams to ever-more perplexing patterns to meet the demand of parallel, multi-mode and multi-functional manipulation of micro-nano objects.

Micro/nanofabrication techniques have gained significant attention in photonic applications since manufacturing approaches directly determine the structural materials of photonic devices and the corresponding optical characteristics, device efficiency, and production costs. Various scalable fabrication methods have been steadily investigated for the manufacturing of photonic devices such as optical absorbers, solar cells, metalenses, metaholograms, and wearable optical devices.