In this study, various Al_xGa_1-xAs nanostructure arrays with variable Al composition are proposed and designed for highly efficient light capture. The optical properties of the proposed nanocone array with variable Al composition have been numerically investigated by COMSOL Multiphysics package based on the finite element method (FEM), and compared with the counterparts of cylinder and conical frustum. The results show that the variable composition Al_xGa_1-xAs nanocones with uniform sublayer distribution thickness can obtain an ultimate efficiency of 37.3%, which is higher than that of the cylindrical and conical frustum structures under the same conditions. In addition, the effects of geometric parameters of nanostructures on the light absorption of nanoarrays with different shape changing components are studied. Taking the variable component Al_xGa_1-xAs nanocone structure as an example, increasing the Al component range in the axial direction of the nanocone can significantly improve the absorption of short-wavelength light, which increases the overall absorption efficiency. In addition, for a specific Al composition distribution range, a uniform thickness distribution design of unit sub-layer in nanocone along the z-axis direction can provide optical absorption enhancement of more than 1.8% and 0.9% over than the decreasing and increasing distribution design. The design principles proposed in this work will provide a reference for selecting appropriate parameters in solar cell applications.

在这项研究中，提出并设计了各种具有可变Al组成的Al _x Ga _1-x As纳米结构阵列，以实现高效的光捕获。利用有限元方法（FEM），通过COMSOL Multiphysics软件包对拟议的Al成分可变的纳米锥阵列的光学性能进行了数值研究，并与圆柱体和圆锥形截头圆锥体的对应物进行了比较。结果表明，Al _x Ga _1-x的可变组成由于具有均匀的子层分布厚度的纳米锥可以获得37.3％的最终效率，高于相同条件下的圆柱形和圆锥形截头圆锥体结构。此外，研究了纳米结构的几何参数对具有不同形状变化成分的纳米阵列的光吸收的影响。取变量分量Al _x Ga _1-x以纳米锥结构为例，增加纳米锥轴向上的Al组分范围可以显着改善短波长光的吸收，从而提高整体吸收效率。此外，对于特定的Al成分分布范围，纳米锥状单元子层沿z轴方向的均匀厚度分布设计与减小和增大的分布设计相比，可以提供超过1.8％和0.9％的光吸收增强。这项工作中提出的设计原则将为在太阳能电池应用中选择合适的参数提供参考。