Journal of the Institute of Electronics Engineers of Korea SD (대한전자공학회논문지SD)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Mach-Zehnder Type $Ti:LiNbO_3$ Traveling-Wave Optical Modulator with m-Section Phase Reversal

m-section의 위상반전이 있는 Mach-Zehnder형 진행파 $Ti:LiNbO_3$ 광변조기

  • Lee, Woo-Jin (Electronics and Telecommunication Research Institute) ;
  • Kim, Kyoung-Am (Dept. of Electronics Eng., The University of Seoul) ;
  • Kim, Woo-Kyung (Dept. of Electronics Eng., The University of Seoul) ;
  • Kim, Chang-Min (Dept. of Electronics Eng., The University of Seoul)
  • 이우진 (韓國電子通信硏究院 光接續모듈팀) ;
  • 김경암 (서울市立大學校 電子電氣工學部科) ;
  • 김우경 (서울市立大學校 電子電氣工學部科) ;
  • 김창민 (서울市立大學校 電子電氣工學部科)
  • Published : 2002.07.01
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Abstract

Mach-Zehnder type traveling-wave optical modulators with 3-section and 5-section phase reversal were designed and fabricated on z-cut $LiNbO_3$ substrates. Optical waveguides were designed by means of the FDM(Finite Difference Method). Design of CPW traveling-wave electrodes were performed by the SOR(Successive Over Relaxation) in the active region and by the CMM(Conformal Mapping) in the input/output section. The optical response R(${\omega}$ calculated based on the measured S-parameters showed the bandwidth of 15GHz centered at 25GHz for the 3-section, and the bandwidth of 22GHz at 45GHz for the 5-section.

z-cut $LiNbO_3$ 기판위에 3-section, 5-section 위상반전 전극을 가진 Mach-Zehnder형 진행파 광변조기를 설계 및 제작하였다. FDM(Finite Difference Method : 유한 차분법)을 이용하여 광도파로를 설계하였으며, MW(Microwave)전극 taper영역의 입${\cdot}$출력단에서는 CMM(Conformal Mapping Method: 등각사상법)을, 변조영역에서는 SOR(Successive Over Relaxation: 반복 이완법)을 이용하여 설계를 수행하였다. 제작된 소자의 S 파라미터를 측정하였다. 측정된 S파라미터를 이용하여 이론적으로 주파수응답 R(${\omega}$)을 구하였다. 3-section 전극의 경우 중심 주파수 25GHz에 ${\sim}$15GHz의 대역폭, 5-section의 경우 중심 주파수 45GHz에 ${\sim}$22GHz의 대역폭을 갖는 bandpass 동작을 나타낼 것으로 예측되었다.

Keywords

References

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