High-speed laser micromachining for fabrication of large-scale freestanding terahertz wire-grid polarizers

Wire-grid polarizers are traditional components for polarization control across the electromagnetic spectrum. Conventional fabrication techniques for terahertz optical elements, including polarizers, remain both costly and time-consuming. Developing efficient, reliable and lower-cost approaches is still an important challenge. In this work, we demonstrate high-speed fabrication of large-scale freestanding THz wire-grid polarizers (WGPs) using a nanosecond laser system equipped with advanced Q-pulse control. By optimizing laser micromachining parameters such as pulse duration, repetition rate and writing speed, we minimized thermal deformation during the production of long metallic wires, enabling scalable manufacturing of freestanding polarizers. The performance of the fabricated WGPs was characterized using THz time-domain spectroscopy (THz-TDS) and compared to numerical simulations.