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本文报道了用以检测采用近乎纯剪切横向(S-H)模式的38°Y-LiNbO_31GHz 压控声延迟线的新实验测量法.所用取向具有高的产速(4800m/s)和大的电声效应,使用一个平面(单个表面)器件结构即可获得高的工作频率和最佳时间延迟调谐灵敏度.此项工作证明,诱发共面E电场的表面电极可提供0.3×10~(-6)/V的相对时间延迟.然而,作为这些器件中的S-H波的漏声表面波(LSAW)和掠面体波(SSBW)两者的同步激励和传播,严重地限制着通过减小电极间距来获得最大延时调制灵敏度(正如在其他类似的SAW器件中所做的那样)的范围.LSAW和SSBW在自由表面几乎以相同的速度传播,传播速度的变化和在表面电极附近的相对衰减率在某些器件结构的两种模式之间产生明显的干扰效应.除了对具有各种表面电极间距的延迟器件提出的测量方法外,由于其他一些干扰因素(包括水银滴落入声通道)使得干扰作用不断侵入,因此,还提供了用以检测LSAW和SSBW之间相对振幅和较小速率差的测量方法.
In this paper, we report a new experimental method for the detection of a 38 ° Y-LiNbO_31GHz voltage-controlled acoustic delay line in near-pure shear (SH) mode with high production rates (4800m / s) and large electroacoustic Effect, the use of a planar (single-surface) device structure results in high operating frequency and optimal time delay tuning sensitivity.This work proves that the surface electrode inducing a coplanar E electric field provides 0.3 × 10 -6 / V. However, the simultaneous excitation and propagation of both the leaky surface wave (LSAW) and the swept body wave (SSBW) as SH waves in these devices severely limit the maximum gain by reducing the electrode spacing Delay modulation sensitivity (as done in other similar SAW devices) .LSAW and SSBW propagate at almost the same velocity on free surfaces, variations in propagation velocity and relative decay rates near the surface electrodes are at some There is a significant interference effect between the two modes of the device structure.In addition to the measurement methods proposed for delay devices with various surface electrode spacings, other disturbing factors (including the mercury dropping into the acoustic channel) Off invasion, therefore, also it provides a relative amplitude between the SSBW and LSAW and smaller velocity difference measurement to detect.