Tecimer, M.; Holldack, K.; Elias, L.R.: Variable reflectivity dielectric mirrors for THz-FEL applications. In: IEEE [Ed.] : 34th International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz 2009, Busan, Korea September 21-25, 2009, 2009. - ISBN 978-1-4244-5417-4
10.1109/ICIMW.2009.5324591
Abstract:
We have constructed and tested multilayer dielectric mirrors with tunable reflectivity to be used as efficient, broad band outcouplers for THz FELs. The test outcoupler mirrors are assembled by stacking up to five cyristalline (z-cut) Quartz wafers separated by vacuum. Reflectivities of 99.5% and a tunability ranging from 0 up to similar to 30% have been measured. In order to attain reflection values >= 99.9% (as a high reflectivity cavity mirror) we employed a hybrid structure that is composed of a metal layer (gold coated) and multiple dielectric layers.