臺灣博碩士論文加值系統

本論文中提出一個新型定向耦合的極化分光器，是利用介電質覆蓋層的方式來製作兩側波導寬高比不同的非對稱定向耦合器，並滿足TM模態的相位匹配條件，讓非對稱波導中的TM模態可以耦合。另一方面，TE模態會因為嚴重的相位不匹配，而不會有顯著的耦合，以此來達到極化分離的效果。最後利用S形的彎曲波導，使得定向耦合器在波導的輸出端可以分離的足夠遠，而不會再出現波導之間相互耦合的現象，以此來設計出微型的極化分光器元件。
從模擬結果顯示我們通過利用介電質覆蓋層的方式，做出了超過20dB的消光比和元件長度小於10 μm 的極化分光器，並且大於10dB消光比的可使用頻寬範圍約為100nm，和寬度誤差容忍度的範圍也大約有77nm。

A polarization beam splitter (PBS) based on asymmetrical directional coupler (ADC) is proposed by utilizing the different aspect ratios between a wide waveguide and a dielectric loaded narrow waveguide. The TM mode is design to be well coupled in the ADC. Meanwhile, the large phase mismatched TE mode results in negligible coupling. Finally, We connect S-bent waveguide at the end of the coupling region to make the two waveguides separated far enough.
The simulation results show that the present PBS has a high extinction ratio of more than 20 dB, and the device length is less than 10 μm. The PBS has a bandwidth range of about 100nm, and fabrication tolerance of about 77nm for the extinction ratio is greater than 10dB.

中文摘要
英文摘要
誌謝
目次
表次
圖次
第一章 緒論
第一節 前言
第二節 研究動機
第二章 理論基礎
第一節 光波導的種類
第二節 波導的模態
第三節 模態的基本電磁理論
第四節 波導的TE波與TM波
第五節 波導的損耗
第六節 極化分光器
第七節 定向耦合器理論
第三章 結構設計與模擬分析
第一節 單模條件設定
第二節 波導寬高比的影響
第三節 波長變化對不同極化狀態耦合效率的影響
第四節 定向耦合器的設計
第五節 頻寬範圍與製程誤差
第四章 結論
參考文獻

[1] N. Madamopoulos, and N. A. Riza, “Directly modulated semiconductor-laser-fed photonic delay line with ferroelectric liquid crystals,” Applied Optics, Vol. 37, No. 8, pp. 1407-1416, 1998.
[2] T. Barwicz, M. R. Watts, M. A. Popovic, P. T. Rakich, L. Socci, F. X. Kartner, E. P. Ippen, and H. I. Smith, “Polarization-transparent microphotonic devices in the strong confinement limit,” Nature Photonics, Vol. 1, No. 1, pp. 57-60, 2007.
[3] B. K. Yang, S. Y. Shin, and D. M. Zhang, “Ultrashort polarization splitter using two-mode interference in silicon photonic wires,” IEEE Photonics Technology Letters, Vol. 21, No. 7, pp. 432-434, 2009.
[4] B. M. A. Rahman, N. Somasiri, C. Themistos, and K. T. V. Grattan, “Design of optical polarization splitters in a single-section deeply etched MMI waveguide,” Applied Physics B-Lasers And Optics, Vol. 73, No. 5, pp. 613–618, 2001.
[5] A. Katigbak, J. F. Strother, and J. Lin, “Compact silicon slot waveguide polarization splitter,” Optical Engineering, Vol. 48, No. 8, 080503, 2009.
[6] L. M. Augustin, R. Hanfoug, J. J. G. M. van der Tol, W. J. M. de Laat, and M. K. Smit, “A compact integrated polarization splitter/converter in InGaAsP-InP,” IEEE Photonics Technology Letters, Vol. 19, No. 17, pp. 1286-1288, 2007.
[7]D. Dai, Z. Wang, and J. E. Bowers, “Considerations for the design of asymmetrical Mach-Zehnder Interferometers used as polarization beam splitters on a sub-micron silicon-on-insulator platform,” Journal of Lightwave Technology, Vol. 29, No. 12, pp. 1808–1817, 2011.
[8] T. K. Liang, and H. K. Tsang, “Integrated polarization beam splitter in high index contrast silicon-on-insulator waveguides,” IEEE Photonics Technology Letters Vol. 17, No. 2, pp. 393–395, 2005.
[9] Y. Tang, D. Dai, and S. He, “Proposal for a grating waveguide serving as both a polarization splitter and an efficient coupler for silicon-on-insulator nanophotonic circuits,” IEEE Photonics Technology Letters, VOL. 21, No. 4, pp. 242-244, 2009.
[10] T. Yamazaki, H. Aono, J. Yamauchi, and H. Nakano, “Coupled waveguide polarization splitter with slightly different core widths,” Journal of Lightwave Technology, Vol. 26, No. 21, pp. 3528-3533, 2008.
[11] X. G. Tu, S. S. N. Ang, A. B. Chew, J. Teng, and T. Mei, “An ultracompact directional coupler based on GaAs cross-slot waveguide,” IEEE Photonics Technology Letters, Vol. 22, No. 17, pp. 1324-1326, 2010.
[12] J. B. Xiao, X. Liu, and X. Sun, “Design of a compact polarization splitter in horizontal multiple-slotted waveguide structures,” Japanese Journal of Applied Physics, Vol. 47, No. 5, pp. 3748-3754, 2008.
[13] P. Wei, and W. Wang, “ATE-TM mode splitter on lithium-niobate using Ti, Ni, and Mgo diffusions,” IEEE Photonics Techmology Letters, Vol. 6, No. 2, pp. 245-248, 1994.
[14] F. Ghirardi, J. Brandon, M. Carre, A. Bruno, L. Meniganx, and A. Carenco, “Polarization splitter based on modal birefringence in InP/InGaAsP optical waveguides,” IEEE Photonics Technology Letters, Vol. 5, No. 9, pp. 1047-1049, 1993.
[15] D. Dai, Z. Wang, and J. E. Bowers, “Ultrashort broadband polarization beam splitter based on an asymmetrical directional coupler,” Optics Letters, Vol. 36, NO. 13, pp. 2590-2592, 2011.
[16] D. Dai, and J. E. Bowers, “Novel ultra-short and ultra-broadband polarization beam splitter based on a bent directional coupler,” Optics Express, Vol. 19, NO. 19, pp. 18614-18620, 2011.
[17] B. E. A. Saleh and M. C. Teich, Fundamentals of Photonics 2nd ed., Wiley, New York 1991.
[18] R. G. Hunsperger, Integrated optics: theory and technology 6eh ed., New York : Springer -Verlag, New York 2009.
[19]O. Bryngdah, “Image formation using self-imaging techniques,” Journal of the Optical Society America, Vol. 63, No. 4, pp. 416-419, 1973.
[20]R. Ulrich, and G. Ankele, “Self-imaging in homogeneous planar optical waveguides,” Applied Physics Letters, Vol. 27, No. 6, pp. 337-339, 1975.
[21] A. Yariv, Quantum Electronics, 3rd edn., Wiley, pp. 623–631, New York 1989.
[22] R.G. Peall, and R.R.A. Syms, “Comparison between strong coupling theory and experiment for 3-ARM directional-couplers in Ti-LinbO3,” Journal of Lightwave Technology, Vol. 7, No. 3, pp.540-554, 1989.
[23] A.J. Baden Fuller, Microwaves, Pergamon, pp. 237-238, Oxford 1979.
[24] S. Somekh, “Theory, fabrication and performance of some integrated optical devices,” PhD Thesis, California Institute of Technology, pp. 46, University Microfilms, Ann Arbor, MI 1974.
[25] S. Somekh, E. Garmire, A. Yariv, and R. G. Hunsperger, “Channel optical-waveguides and directional-couplers in GaAs-imbedded and ridged,” Applied Optics, Vol. 13, No. 2, pp. 327-330, 1974.