Chinese Optics Letters, 2015, 13 (12): 123101, Published Online: Sep. 12, 2018
Using lead germanium telluride as a high-index coating material in the mid-wavelength infrared narrow bandpass filters Download: 801次
310.1620 Interference coatings 310.3840 Materials and process characterization 310.6188 Spectral properties 310.4165 Multilayer design
Abstract
In our investigation, lead germanium telluride, which is a pseudo-binary alloy of IV-VI narrow-gap semiconductor compounds of PbTe and GeTe, can be used in the fabrication of mid-wavelength infrared narrow bandpass filters as a high-index coating material, due to its high refractive index, lower absorption, and tunability of fundamental absorption edges. It is demonstrated that a half-width of 160 nm and a better rejection ratio can be obtained for a simple 8-layer double cavity filter with a central wavelength at 4 μm, compared with a half-width of 390 nm for those conveniently fabricated using Ge as high-index material.
Ping Xie, Bin Li, Suying Zhang, Dingquan Liu. Using lead germanium telluride as a high-index coating material in the mid-wavelength infrared narrow bandpass filters[J]. Chinese Optics Letters, 2015, 13(12): 123101.