【摘要】 采用多载流子模型,分析了熔融石英在空气中热及电场诱导的物理过程,证明了耗尽区是由正带电层、电离层和负耗尽层组成.前两者的空间电荷是H3O+,O+和Al++等,后者的空间电荷是≡Si—O-.电离层的强弱决定了耗尽区的热稳定性.推导了耗尽区的离子浓度分布,结果表明,正、负空间电荷层近似均匀分布,耗尽区的自建电场近似三角状分布,它的最大值在石英样品内部.采用该模型可证明,二阶极化率和二次谐波的转换效率与诱导时所加外界电压分别成平方根和平方关系.更多还原

【Abstract】 Using the multiple\|carrier model, the process for thermal/electric\|field poling in the fused silica is analyzed. The depletion region is proved to be composed of a positive charged layer, an ionosphere layer and a negative depletion layer. The space\|charges in two former layers are H\-3O\++,O\++,Al ++ and others, and the space\|charge in the latter is \{≡Si—O\+-. The\} thermal stability of the depletion region is determined by the strength of the ionosphere. In addition, the ion density distribution in the depletion region is derived. The results show that both the positive and the negative space\|charge layers are approximately well\|distributed, and the self\|built electric field in the depletion layer is approximately distributed in triangle\|form, the maximum of which is located inside the sample. This model proves that the second order susceptibility and the conversion efficiency of the second harmonic are proportional to the square\|root and square of the applied dc voltage, respectively.更多还原