Ultrabroadband suppression of mid-infrared reflection losses of a layered semiconductor by nanopatterning with a focused ion beam

• DOI: 10.1364/oe.433703
• Publication Date: 2021-08-18T08:30:15Z
• Authors: Matthias Hagner; Philipp Sulzer; Andreas Liehl; Moritz Cimander; Hannes Kempf; Annika Bitzer; Alexa Herter; Alfred Leitenstorfer
• Keywords: Fresnel equations; Optical rectification; Reflection

Moth-eye structures are patterned onto gallium selenide surfaces with sub-micrometer precision. In this way, Fresnel reflection losses suppressed to below one percent within an ultrabroad optical bandwidth from 15 65 THz. We tune the geometry by rigorous coupled-wave analysis. Subsequently, ablation a Ga+ ion beam serves write optimized in areas covering 30 μm. The benefits demonstrated via rectification of femtosecond laser pulses under tight focusing, resulting emission phase-stable transients mid-infrared. analyze performance antireflection coating directly time domain ultrabroadband electro-optic sampling.