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Title: Low-loss hybrid germanium-on-zinc selenide waveguides in the longwave infrared
Abstract The longwave infrared (LWIR) range, which spans from 6 µm to 14 µm, is appealing for sensing due to strong molecular fingerprints in this range. However, the limited availability of low-loss materials that can provide higher-index waveguiding and lower-index cladding in the LWIR range presents challenges for integrated photonics. In this work, we introduce a low-loss germanium-on-zinc selenide (GOZ) platform that could serve as a versatile platform for nanophotonics in the LWIR. By bonding high-quality thin-film germanium (Ge) to a zinc selenide (ZnSe) substrate, we demonstrate transparency from 2 µm to 14 µm and optical losses of just 1 cm−1at 7.8 µm. Our results demonstrate that hybrid photonic platforms could be invaluable for overcoming the losses of epitaxially grown materials and could enable a wide range of future quantum and nonlinear photonics.  more » « less
Award ID(s):
2349259
PAR ID:
10489582
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
De Gruyter
Date Published:
Journal Name:
Nanophotonics
Volume:
0
Issue:
0
ISSN:
2192-8606
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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