Sio Weng Hong, Verdi Carla, Poncé Samuel, Giustino Feliciano
Department of Chemistry, Physical and Theoretical Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom.
Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, United Kingdom.
Phys Rev Lett. 2019 Jun 21;122(24):246403. doi: 10.1103/PhysRevLett.122.246403.
We develop a formalism and a computational method to study polarons in insulators and semiconductors from first principles. Unlike in standard calculations requiring large supercells, we solve a secular equation involving phonons and electron-phonon matrix elements from density-functional perturbation theory, in a spirit similar to the Bethe-Salpeter equation for excitons. We show that our approach describes seamlessly large and small polarons, and we illustrate its capability by calculating wave functions, formation energies, and spectral decomposition of polarons in LiF and Li_{2}O_{2}.
我们从第一性原理出发，开发了一种形式体系和计算方法来研究绝缘体和半导体中的极化子。与需要大超胞的标准计算不同，我们求解一个涉及声子和电子 - 声子矩阵元的久期方程，该方程来自密度泛函微扰理论，其思路类似于激子的贝特 - 萨尔皮特方程。我们表明，我们的方法能够无缝描述大极化子和小极化子，并通过计算LiF和Li₂O₂中极化子的波函数、形成能和光谱分解来说明其能力。
