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

The Institute of Electronics and Information Engineers (대한전자공학회)
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Design of $Ti:LiNbO_3$ Three-Waveguide Optical Switch with Center-Waveguide Fed

가운데 도파로 입사된 $Ti:LiNbO_3$ 세 도파로 광스위치의 설계 및 제작

  • 허창열 (서울市立大學校 電子電氣工學部科) ;
  • 한영탁 (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 : 2000.06.01
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Abstract

An optical switch composed of identical, equally-spaced $Ti:LiNbO_3$ three-waveguides was designed and fabricated. Patterned Ti was diffused into z-cut $LiNbO_3$ substrates. $SiO_2$ buffer layer was evaporated to reduce the propagation loss of TM mode, and Al electrodes of CPW structure were built on the layer for switching of the guided beam. The optical switching phenomenon was confirmed when a beam of ${\lambda}=1.3{\mu}m$ was launched into the center waveguide and an electric field was applied to detune the three waveguides symmetrically.

등간격, 동일 구조의 $Ti:LiNbO_3$ 세 도파로를 이용한 광스위치를 설계하고 제작하였다. 공도파로는 z-cut $LiNbO_3$ 기판상에 Ti를 내부 확산시켜 제작하였다. TM 모드 전파 손실을 줄이기 위하여 도파로 위에 $SiO_2$ 박막을 증착시킨 후, 광스위칭을 위하여 CPW(Coplanar Waveguide)구조 Al 전극을 형성시켰다. 가운데 도파로에 입사된 ${\lambda}=1.3{\mu}m$ 광에 대하여 세 도파로가 대칭적으로 detuning 되도록 전계 인가시 광 스위칭이 일어남을 확인하였다.

Keywords

References

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