Investigation of the cracks on the surface of proton-exchanged LiNbO3 wave-guides
-
1.
School of Optic-Electronic Information, UESTC, Chengdu 610054, China;
-
2.
Department of Physics and Electronic Information, West China Normal University, Nanchong 637002, China
-
Corresponding author:
LIU Yong-zhi, yzliu123@uestc.edu.cn
;
-
Received Date:
2005-07-07
Accepted Date:
2005-10-31
-
Abstract
In order to investigate the generation mechanism of the cracks on the surface of proton-exchanged(PE) wave-guides on the x-cut lithium niobate substrate and the influence on the characteristics of wave-guide.The crystal microstructure,the intensity of the cracks on the surface,the existing manner of hydrogen ion and the variation of density of the annealing proton-exchanged(APE) wave-guide are studied by means of contrast experiments,observation on the surface of wave-guide,XRD(X-ray diffraction) analysis of the crystal phase in the wave-guide,infrared absorption spectra analysis of wave-guide,and so on.The results show that the cracks are made by the stress parallel with the principal cleavage plane of lithium niobate,which have four characteristics:made in the PE process,parallel with each others,deteriorated in proportion to the time of PE process and being ameliorated somewhat in the annealing process.It is also shown that the cracks are the macroscopical representation of the stress and that the annealing process could influence the existing manner of hydrogen ion and its density variation,alter the crystal phases and the stress in the wave-guide,and improve the performance of the wave-guide.It is concluded that multiple-phase coexistence and the difference of the crystal lattice coefficient resulted in the stress and then lead to the crackand that the smallest distortion in crystal lattice,the lowest stress and the α phase wave-guide may have the lowest possibility to bring out crack,and can improve the performance of the wave-guide.
-
-
References
[1]
|
ZHANG D L,DING G L,GAI Y M et al.Proton-exchanged opticalwaveguide[J].Progress in Physics,2001,21(1):45~65(in Chinese). |
[2]
|
JACKEL J L.Proton exchange:past,present,and future[J].SPIE,1991,1583:54~63. |
[3]
|
YIN Y J.The handbook of chenistry used in college[M].Ji'nan:Shandong Science and Technology Press,1985.1092(in Chinese). |
[4]
|
YIN Y J.The handbook of chemistry used in college[M].Ji'nan:Shandong Science and Technology Press,1985.1093(in Chinese). |
[5]
|
WEIS R S,GAYLORD T K.Summary of physical and crystal structure[J].Appl Phys,1985,36(4):191~203. |
[6]
|
LI Sh T.The elements of crystal XRD[M].Beijing:Metallurgical Industry Press,1990.19~32(in Chinese). |
[7]
|
LI J Z.Crystal optics[M].Beijing:Beijing University of Technology Press,1989.21~23(in Chinese). |
[8]
|
LONI A,HAY G,de la RUE R M et al.Proton-exchanged LiNbO3 waveguides:the effects of post-exchange annealing and buffered melts as determined by infrared spectroscopy,optical waveguide measurements,and hydrogen isotopic exchange reactions[J].IEEE Journal of Lightwave Technology,1989,7(6):911~919. |
-
-
Proportional views
-