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Design of an X-cut thin-film lithium niobate waveguide as a passive polarization rotator
The transverse-electric and transverse-magnetic modes of an X-cut thin-film lithium niobate waveguide vary in effective indices and exchange power when the waveguide makes an oblique angle with its crystallographic Z-axis, i.e. its optics axis. We leverage this phenomenon to design a passive fundamental-mode polarization rotator. In our design, the lithium niobate waveguide is tilted at an optimum angle with respect to its Z-axis, such that material anisotropy induces phase-matched polarization conversion. We discuss the rotator’s ideal-device length, crosstalk, and bandwidth. The proposed design yields compact (shorter than 1 mm), low-loss, passive polarization rotators for telecom wavelengths.
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- Award ID(s):
- 1807735
- PAR ID:
- 10390416
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 29
- Issue:
- 26
- ISSN:
- 1094-4087
- Page Range / eLocation ID:
- 44174
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1364/OE.445412
