论文部分内容阅读
我们采用了在衬底表面和与衬底表面垂直方向施加电场的方法,研究了三片高耦合切型LiNbO_3的可变延时特性。发现了旋转16.5°LiNbO_3切片具有与38X型材料相等的线性延时系数。但在实际应用中,其效应太小。本器件是由位于声通道上导电电极构成的SAW延迟线组成。当改变加于电极和衬底背面的不锈钢接地之间的电压时,其速度变化呈线性的。当衬底厚0.16mm时,观察到速度相对变化为9×10~(-7)/V,相当于灵敏度γ=1.36×10~(-10)m/V。这是至今我们所知的灵敏度最高的器件。与我们早期的38X切型LiNbO_3的灵敏度1.4×10~(-10)m/V相当,且线性度很好,通过二阶导数推得它对时间的曲线斜率为10~(-3)。平面型时间延迟器件灵敏度的简单模型与实验条件有关。我们对两种几何结构的色散进行了计算,结果表明:对许多应用来说,这种差别是微不足道的。
We used a method of applying an electric field perpendicular to the substrate surface and the substrate surface to study the variable delay characteristics of three high-coupling cut LiNbO_3. It was found that the rotating 16.5 ° LiNbO 3 slice has a linear delay coefficient equal to the 38X material. However, in practical applications, the effect is too small. This device consists of a SAW delay line located on the conductive channel of the acoustic channel. When changing the voltage applied between the electrodes and the stainless steel ground at the back of the substrate, the velocity changes linearly. When the substrate thickness is 0.16mm, the relative velocity change is observed to be 9 × 10 -7 / V, which corresponds to the sensitivity of γ = 1.36 × 10 -10 m / V. This is by far the most sensitive device we know. Compared with the sensitivity of 1.4 × 10 ~ (-10) m / V, the linearity of LiNbO_3 is very good. The slope of the curve is 10 ~ (-3) with the second derivative. The simple model of planar time delay device sensitivity is related to the experimental conditions. We calculated the dispersion of the two geometries and the results show that for many applications this difference is negligible.