S型彎曲波導與微米小球共振腔之光耦合效率研究

江信東(Hsin-Tung Chiang)

指導教授 ： 戴朝義

國立中央大學/理學院/光電科學研究所/碩士(2007年)

摘要

本論文提出一種新的共振器耦合器結構，主要利用S型彎曲波導所造成的彎曲損失將能量耦合進入微米小球共振腔，此結構可積體化構裝於Si晶片上具有較佳的機械強度等優點。
在實驗模擬上我們得到與微米小球的耦合效率最高可達35%以上，而實驗的量測上，S型彎曲波導在彎曲半徑為1500微米且彎曲角度為41度時的彎曲損失約為13dB/cm，而在角度為40度時彎曲損失開始明顯上升的趨勢，與利用光束傳播法模擬所得之結果吻合。

關鍵字

S型彎曲波導 ； 彎曲損失 ； 光束傳播法 ； 微米小球 ； 保角轉換

並列摘要

We have designed and fabricated an S-bend waveguide structure which enables one to excite the Whispering Gallery Modes (WGMs) in microspheres. The highest coupling efficiency found is estimated to be about 35%, and the designed structure has high position and wavelength tolerance. By misplacing the microsphere by 15um only results in 6% coupling efficiency degradation; while 10nm wavelength drift results in 3dB/cm coupling efficiency degradation.
Preliminary experimental result shows that the design is in close agreement with the simulation using beam propagation method (BPM). II

並列關鍵字

microsphere ； conformal transformation ； WGMs ； bending loss ； BPM ； Bending waveguide

參考文獻

“ Pedestal antiresonant reflecting waveguides for robust coupling to microsphere resonators and for microphotonic circuits” OPTICS LETTERS, Vol.25, No.1,pp.73,January 2000

[2] M. L.Gorodetsky and V.S.Ilchenko“ Optical microsphere resonators: optimal coupling to high-Q whispering-gallery modes”J.Opt.Soc.Am.B ,Vol.16,No.1/January 1999

[4] Vladimir S. Ilchenko, X. Steve Yao,and Lute Maleki,

[5] N. Dubreuil , J.C. Knight , D. K. Leventhal , V.Sandoghdar , J. Hare , and V. Lefevre, “Eroded monomode optical fiber for whispering-gallery mode excitation in fused-silica microspheres”OPTICS LETTERS, Vol.20,No.8,pp.813,April 1995

[6] M.L.Gorodetsky,A.A.Savchenkov,and V.S.Ilchenko“Ultimate Q of optical microsphere resonators”,Optics Letters,Vol.21,No.7,1996