AlxGa1-xAs crystals with direct 2 eV band gaps from computational alchemy

作者：Chang K Y Samuel; von Lilienfeld O Anatole^*

来源：Physical Review Materials, 2018, 2(7): 073802.

DOI：10.1103/PhysRevMaterials.2.073802

We use alchemical first-order perturbations for the rapid yet robust prediction of band structures. The power of the approach is demonstrated for the design challenge of finding AlxGa1-xAs semiconductor alloys with large direct band gap using computational alchemy within a genetic algorithm. Dozens of crystal polymorphs are identified for x > 2/3 with direct band gaps larger than 2 eV according to HSE approximated density functional theory. Based on a single generalized gradient approximated density functional theory band-structure calculation of pure GaAs we observe convergence after visiting only similar to 800 crystal candidates. The general applicability of alchemical gradients is demonstrated for band-structure estimates in III-V and IV-IV crystals as well as for H-2 uptake in Sr and Ca-alanate crystals.

• 出版日期2018-7-23