Three‐dimensional printing technologies for terahertz applications: A review

Abstract

Three-dimensional (3D) printing technologies enables fast prototyping of complex 3D objects with ever improving printing qualities. To date, 3D printing has been found useful in areas such as manufacturing, industrial design, aerospace, dental and medical industries, and many others. In this article, we review recent advances of 3D printing technologies for terahertz (THz) applications. Different 3D printing technologies and printable materials are first discussed and compared. 3D-printed THz components and devices, which are categorized as waveguides/fibers, antennas, and quasi-optical components, are further demonstrated. It is found that the performances and functionalities of 3D-printed THz devices have been greatly enhanced, while the operating frequencies have been increased from the lower end of THz range to over 1 THz region. With further development of novel materials and printing techniques, it is believed that 3D printing technologies will play an important role in the realization of THz components for efficient control and manipulation of THz waves. K E Y W O R D S

Terahertz waves dynamic diffusion in 3D printed structures

“…In general, this technology is able to create 3D objects through additive manufacturing (AM) methods, where the final product is obtained layer by layer. AM concepts have been applied in a multitude of ways, bringing a wide range of 3D printing technologies allowing cheap, rapid and customisable fabrication of THz components made of polymers, ceramics, metals, and composites 34 , 35 .…”

“…This process is repeated, until the whole object is complete. Thanks to the continuous innovation of hardware, materials, and processes, structures with minimum features sizes and tolerances around 100–200 m can be fabricated by using FDM, providing a low-cost solution for rapid manufacturing of THz components working in the lower frequency region of the THz band 34 – 36 .…”

BaSrTiO 3 ceramic‐polymer composite material lens antennas at 220–330 GHz telecommunication applications

“…However, both principles need either large antenna arrays [3 ] or lens antenna [4 ] structures on the air interface. Most of the presented lens antennas are build conventional high resistivity silicon [2, 4 ] or pure polymer materials [5–13 ] where typically lens material shapes, small details or macroscopic porosity are controlled by various fabrication methods. In addition, alumina material fabricated lens is presented in [14 ].…”

In-line evanescent-field-coupled THz bandpass mux/demux fabricated by additive layer manufacturing technology

“…Additive manufacturing technology, also known as 3D printing, is a valuable technique for the fabrication of complex optical components for the terahertz (THz) range of frequencies [1,2]. The impact of such devices has spread across a wide range of areas, including skin characterisation [3], microscopy [4], polarization control [5], photonic crystals [6,7], beam formation [8,9], and THz fibers [10,11], just to name few.…”

“…Bandpass filters are some of the key components needed for the manipulation of THz light. Designs to produce them hitherto incorporate fundamental principles from guided-mode resonances [13], Bragg resonators [11,14], and two-dimensional periodic structures [6] among others [1,2,15]. Coupled mode waveguides have proved useful in the microwave regime [16][17][18], and recently this technology has been demonstrated at THz frequencies [19,20].…”