【摘要】 本文报导在Ti扩散LiNbO₃波导中,由光学导波和声表面波实现的声光衍射实验。实验中,我们测量了两种TE（TE₀,TE₁）模的主要衍射级光强相对声功率的分布,同时给出实用的计算声功率公式:Pa=(4△n²/n⁶P_3J²K)/LP_R。并在声光品质因数Q=2.5条件下,近似选取了Raman-Nath衍射0级光束相消的位相条件,进行了参数处理。计算了声功率、位移和应变。利用光学导波和声表面波衍射作用的集成光学声光器件,可用于光调制,偏转和开关。过去,这方面有代表性的研究工作是Kuhn等人在玻璃膜波导上的声光工作和Schmidt等人在LiNbO₃（LN）扩散波导上的声光工作。更多还原

【Abstract】 The acousto-optic diffraction experimental results of guided optical waves and acoustic surface waves in the Ti-diffused LiNbO3 waveguides are reported in this paper. Phe intensity of two TE modes (TE0, TE1) varying with the acoustic power is measured. For the zero-order beam, modulation approximate to 100% is obtained at 68 mW acoustic power. After simple deduction, acoustic surface displacement is obtained:Then, the useful equation of acoustic power is given:A /vt 2__ ^L " T 7Jtt--------u.,2 ,r J^l R,where K is the acoustic wave vector, n is the refractive index, P3J is the photoelastic constant, L is the acoustic active aperture length and PR is a constant.In our experiments, the practical standard of Raman-Nath diffraction (Q<^) is used. Under the condition of Q = 2.5, the phase condition of the depletion of zero-order beam of Raman-Nath diffraction is approximately selected to be 2nAn L/K = 2.3, where An is the increment of the refractive index and K is the optical wavelength. Therefore we obtain Jn = 4.7xlO~30 From An, the values of acoustic surface waves power Ptt, acou stic surface displacement Uj and acoustic strains Sj are calculated. Hence, we have P - fi9mW TT^ - 4. 7 10~lom /? -4 Q 10~5J. u - \J III vv, \J 2- ^t.l J-v* *?? 2 - ? ?^ -"-^ ?更多还原