| URN |
etd-0527113-152017 |
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| Author |
Jia-Shing Jhang |
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| Author's Email Address |
No Public. |
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| Statistics |
This thesis had been viewed 5569 times. Download 0 times. |
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| Department |
Electro-Optical Engineering |
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| Year |
2012 |
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| Semester |
2 |
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| Degree |
Master |
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| Type of Document |
|
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| Language |
zh-TW.Big5 Chinese |
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| Title |
Improved SOI Micro-Racetrack Resonators Using Taper with Offset Structure |
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| Date of Defense |
2013-06-24 |
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| Page Count |
71 |
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| Keyword |
racetrack resonator
quality factor
critical coupling condition
ring resonator
|
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| Abstract |
In order to achieve high-density integration and large free spectral range (FSR), the size of the microring resonators (MRRs) should be reduced. However, the bending loss raises as the microring resonators are too small. In addition, the gap between the straight waveguide and the ring waveguide in MRR structures must be very small to achieve the critical coupling condition due to the weak coupling coefficient. By utilizing the micro-racetrack resonator structures with strong coupling abilities, we can enlarge the critical gap and improve the fabrication tolerance. However, the micro-racetrack resonators may suffer higher losses resulted from the mode conversion between the straight and bent waveguides. In this paper, we widen the bent waveguide and adopt taper with offset structure to reduce the radiation loss and mode conversion loss of micro-racetrack resonators.
In this thesis, we first use the 2-D finite-difference time-domin (FDTD) method with the effective index method (EIM) to obtain the transmission spectra of the SOI micro-racetrack resonators. The transmission spectra are then fitted by using the time-domain coupled mode theory (CMT) to obtain the quality factors of the SOI micro-racetrack resonators. We have demonstrated that the taper structure for the SOI micro-racetrack resonators can enlarge the critical gap by 0.025 μm and enhance twice the total quality factor. Finally, we employ a taper with offset structure between the bent and straight waveguides. In addition, the transmission waveguide is designed of the same structure to form symmetric SOI micro-racetrack resonators. The critical gap is shown to be increased by 0.15 μm, and the total quality factor is enhanced by six times. |
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| Advisory Committee |
Hung-wen Chang - chair
Jau-Sheng Wang - co-chair
Jui-Yang Feng - co-chair
Chin-Ping Yu - advisor
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| Files |
Indicate in-campus at 99 year and off-campus access at 99 year. |
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| Date of Submission |
2013-06-27 |
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