Ab initio electronic stopping power for protons in Ga0.5In0.5P/GaAs/Ge triple-junction solar cells for space applications

Motivated by the radiation damage of solar panels in space, firstly, the results of Monte Carlo particle transport simulations are presented for proton impact on triple-junction Ga0.5In0.5P/GaAs/Ge solar cells, showing the proton projectile penetration in the cells as a function of energy. It is followed by a systematic ab initio investigation of the electronic stopping power for protons in different layers of the cell at the relevant velocities via real-time time-dependent density functional theory (RT-TDDFT) calculations. The electronic stopping power is found to depend significantly on different channeling conditions, which should affect the low velocity damage predictions, and which are understood in terms of impact parameter and electron density along the path. Additionally, we explore the effect of the interface between the layers of the multilayer structure on the energy loss of a proton, along with the effect of strain in the lattice-matched solar cell. Both effects are found to...本研究受太空太阳能电池辐射损伤问题启发，首先针对质子入射三结Ga₀.₅In₀.₅P/GaAs/Ge太阳能电池的场景，展示了蒙特卡洛粒子输运模拟（Monte Carlo particle transport simulations）的结果，呈现了电池内质子入射粒子的穿透深度随能量的变化规律。随后，本研究通过实时含时密度泛函理论（real-time time-dependent density functional theory, RT-TDDFT）计算，在对应入射速度条件下，系统开展了电池各层内质子的电子阻止本领（electronic stopping power）的从头算（ab initio）研究。研究发现，电子阻止本领显著依赖于不同沟道条件（channeling conditions），该效应会对低速损伤预测产生影响，且可通过碰撞参数（impact parameter）以及粒子运动路径上的电子密度对其机制进行阐释。此外，本研究还探究了多层结构各层间的界面对质子能量损失的影响，以及晶格匹配太阳能电池中的晶格应变效应。两种效应均被发现……