Machinable ceramic for high performance and compact THz optical components

Abstract

The properties of Shapal Hi-M Soft, an aluminum nitride based ceramic, as a material for THz optical components are investigated and compared with other ceramic materials. Shapal is a low-cost and machinable ceramic with a high-refractive index and low losses at THz frequencies: n = 2.65, alpha = 0.4 cm(-1). To demonstrate the shaping capabilities, a Fresnel lens is fabricated with a micro-milling system. Additionally, a prism as an example of a bulk component is demonstrated. Both a THz time domain spectrometer and a vector network analyzer (0.75-1.1 THz) are used for the optical characterization and the absorption coefficient is precisely obtained in the VNA frequency range. Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License.