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

대한전자공학회 (The Institute of Electronics and Information Engineers)
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Mach-Zehnder형 진행파 Ti:$LiNbO_3$ 광변조기의 제작 및 변조응답 추정

Fabrication of Mach-Zehnder Type Traveling-Wave Ti:$LiNbO_3$ Optical Modulator and Estimation of Frequency Response

  • 한영탁 (한국전자통신연구원 실리카광부품팀) ;
  • 이우진 (서울시립대학교 전자전기공학부과) ;
  • 고병국 (서울시립대학교 전자전기공학부과) ;
  • 이병권 (서울정수기능대학교) ;
  • 김창민 (서울시립대학교 전자전기공학부과)
  • 발행 : 2001.11.01
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초록

Mach-Zehnder 간섭기를 이용한 Ti:$LiNbO_3$ 진행파 광변조기를 설계 및 제작하였다. FDM을 이용하여 광도파로의 최적 설계치를 추출하였다. CPW 진행파전극의 MW 유효굴절률 및 특성임피던스를 정합시키기 위하여 taper 영역의 입·출력단에서는 CMM을, 변조영역에서는 FEM으로 설계를 수행하였다. 제작된 소자의 MW 특성으로는, S 파라미터로부터 감쇠상수 ${\alpha}_m$=0.05426 $\sqrt{f}$, MW 유효굴절률 $N_{eff}$=2.2025, 특성임피던스 $Z_c$=39 ${\Omega}$이 추출되었다. MW 특성으로부터 계산한 주파수응답 $R({\omega})$의 3 dB 변조대역폭은 ~10GHz으로 예측되었다.

Mach-Zehnder type traveling-wave Ti：LiNb $O_3$ optical modulators were designed and fabricated. Optimum parameters of optical waveguides were calculated by means of the FDM. Design of CPW traveling-wave electrodes were performed by the FEM in the active region and by the CMM in the input/output section to obtain the conditions of MW effective index and impedance matching. From the measured S parameters, MW characteristics of the traveling-wane electrodes were extracted to be ${\alpha}_m$=0.05426 $\sqrt{f}$, $N_{eff}$=2.2025, and $Z_{c}$=39 ${\Omega}$. The calculated optical response R($\omega$) showed the 3 dB bandwidth of 10 GHz.z..

키워드

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