Abstract-Broadband terahertz ZnO photonic crystals fabricated by 3D printing

Carmen R.Tubío, José Antonio Nóvoa, Jorge Martín, Francisco Guitián, José Ramón Salgueiro, Alvaro Gil, 

https://www.sciencedirect.com/science/article/pii/S0272884218334837

ZnO has been demonstrated to be a promising material for optoelectronic applications in the terahertz (THz) spectral range. However, there have been no reports regarding the fabrication of ZnO structures to control THz radiation, as photonic crystal (PCs) materials. Here, we focus on the development of a functional ZnO PCs for the THz band. The functionality is provided by the design that is based on a woodpile lattice with the appropriate periodicity for the THz region. Using a three-dimensional (3D) printing technique, we fabricate 3D ZnO based PCs with an effective lattice constant to generate a bandgap at the THz region. The functionality of the resulting PC was evaluated using THz time-domain spectroscopy combined with theoretical simulations. The results demonstrate the 3D woodpile lattice structure has good optical properties in the THz frequency region. These results serve as a step for the development of new THz functional devices for optoelectronics applications.

Abstract-3D printing of Al2O3 photonic crystals for terahertz frequencies

Carmen Rial Tubio,   José Antonio Novoa,   Jorge Martín,  Francisco Guitian,   José Ramón Salgueiro and   Alvaro Gil  

RSC Adv., 2015, Accepted Manuscript

DOI: 10.1039/C5RA22737B
Received 29 Oct 2015, Accepted 23 Dec 2015
First published online 23 Dec 2015
http://pubs.rsc.org/en/content/articlelanding/2015/ra/c5ra22737b#!divAbstract

Reported here is the fabrication and characterization of a three-dimensional photonic crystal for terahertz frequencies based on 3D printing of Al₂O₃. Specific inks containing Al₂O₃, the material required for the structure, are synthesized with the viscosity and rheological properties necessary to be extruded through nozzles of micrometric section. The process is completed by a thermal sintering to obtain compact structures. SEM measurements are performed to evaluate the quality of the structures and measure the geometrical parameters. Finally, the presence of the band gap is demonstrated by THz time-domain spectroscopy.