Ga_3PO_7晶体结构及声表面波特性研究

Study on the Structure and Surface Acoustic Wave Properties of Ga_3PO_7 Crystal

本文采用第一性原理方法研究了磷酸三镓(Ga3PO7)晶体的几何结构和电子结构。计算了该晶体X,Y,Z切型传播角度为0～180°的声表面波速度,机电耦合系数和能流角。第一性原理研究表明该晶体具有较强的共价键结构特征,其带隙为3.646 eV,属于直接带隙材料。计算结果表明其声表面波速度范围为3620～3850 m/s,与石英晶体相当,但其Y切型的机电耦合系数最高可达1.075%,是石英晶体的三倍。

The geometry structure and electronic structure of trigallium phosphate single Ga3PO7crystal, were studied using first principle theory method. The surface acoustic wave （SAW） velocity, electronmechanical coupling factor and power flow angle （PFA） of Ga3PO7 were calculated for the propagation direction from 0° to 180° in X-cut, Y-cut and Z-cut. The results show that the crystal has strong covalent bond structure characteristics. The direct band gap is 3. 646 eV. It is found that the SAW velocity of Ga3PO7 is between 3620 m/s and 3850 m/s, and the electronmechanical coupling factor in Y-cut is up to 1. 075%, which is three times of that of alpha quartz crystal.