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We introduce a new decomposition of Weinstein 4-manifolds called multisections with divides and show these can be encoded diagrammatically by a sequence of cut systems on a surface, together with a separating collection of curves. We give two algorithms to construct a multisection with divides for a Weinstein 4-manifold, one starting with a Kirby-Weinstein handle decomposition and the other starting with a positive, allowable Lefschetz fibration (PALF). Through the connections with PALFs, we define a monodromy of a multisection and show how to symplectically carry out monodromy substitution on multisections with divides.
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Compact Inverse Designed Integrated 1 x 3 Silicon Nitride Balanced Optical Power Splitter
We designed a compact integrated Silicon Nitride 1 x 3 balanced optical power splitter using density-based topology optimization with built-in fabrication constraints. We experimentally validate our design on a commercial foundry process with a splitting ratio of 30-36-33 % and an insertion loss of 2.48 dB across two wafers
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- Award ID(s):
- 2052808
- PAR ID:
- 10416495
- Date Published:
- Journal Name:
- IEEE IPC conference 2022
- Page Range / eLocation ID:
- 1 to 2
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/IPC53466.2022.9975711
