Compact Polarization Rotators Based on Silicon Nanowire Waveguides
碩士 === 國立交通大學 === 光電工程學系 === 101 === A novel mode-coupling-based polarization rotator for silicon wire waveguides is presented. This device consists of a Si3N4 nano-waveguides located at one corner of a silicon wire. To obtain two lowest-order eigenmodes with polarization states of ?b45?a, the thick...
| Main Authors: | , |
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| Other Authors: | |
| Format: | Others |
| Language: | zh-TW |
| Published: |
2012
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| Online Access: | http://ndltd.ncl.edu.tw/handle/rw99a7 |
| Summary: | 碩士 === 國立交通大學 === 光電工程學系 === 101 === A novel mode-coupling-based polarization rotator for silicon wire waveguides is presented. This device consists of a Si3N4 nano-waveguides located at one corner of a silicon wire. To obtain two lowest-order eigenmodes with polarization states of ?b45?a, the thickness of Si3N4 structure is 100 nm as that of Si layer is 220nm at the wavelength of 1550 nm. The effective indices for these two modes obtained by the finite element method are 1.558 and 1.531, respectively, and then the corresponding half-beat length is 28.56 ?慆. 5-?慆 long tapers are inserted in-between this structure and the input/output waveguide to minimize the coupling loss due to mode mismatch. Simulation results obtained by three-dimensional finite difference time domain method show that this device has the insertion loss of 0.3 dB at the wavelength of 1550 nm, and the polarization extinction ratio of over 20 dB at the wavelength range of 1500 -1600 nm.
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