Microstructured sapphire shaped crystals for anitiresonant and bandgap terahertz waveguidingG.M. Katyba, N.V. Chernomyrdin, K.I. Zaytsev and V.N. KurlovEPJ Web Conf., 195 (2018) 09003DOI: https://doi.org/10.1051/epjconf/201819509003