Review of nanoimprinted photonics

Nanoimprint lithography (NIL) has emerged as a powerful tool for patterning nanoscale structures with high precision, low-cost, and large-scale manufacturing. In photonics, NIL enables the creation of complex optical structures such as gratings, metamaterials, photonic crystals, and waveguides. These nanoscale features are critical for manipulating light at sub-wavelength scales, offering enhanced control over optical properties such as dispersion, polarization, and transmission. NIL's high-resolution patterning capability makes it particularly attractive for fabricating large-area photonic devices with high precision and repeatability. A wide range of applications, including integrated photonic circuits, optical sensors, and advanced light management in displays and solar cells, are now the focus of extensive research and discussion. By enabling the precise engineering of refractive index profiles and light-matter interactions, NIL continues to play a crucial role in advancing the performance and functionality of next-generation photonic systems. This review explores the fundamental principles of NIL and its recent developments. In addition, other patterning techniques related to photonics patterning and fabrication are briefly discussed. We will then focus on the applications in photonics and the advantages and challenges associated with this technique.