The Makineni Theoretical Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA.
Phys Rev Lett. 2012 Dec 7;109(23):236601. doi: 10.1103/PhysRevLett.109.236601. Epub 2012 Dec 4.
We compute the bulk photovoltaic effect (BPVE) in BiFeO(3) using first-principles shift current theory, finding good agreement with experimental results. Furthermore, we reconcile apparently contradictory observations: by examining the contributions of all photovoltaic response tensor components and accounting for the geometry and ferroelectric domain structure of the experimental system, we explain the apparent lack of BPVE response in striped polydomain samples that is at odds with the significant response observed in monodomain samples. We reveal that the domain-wall-driven response in striped polydomain samples is partially mitigated by the BPVE, suggesting that enhanced efficiency could be obtained in materials with cooperative rather than antagonistic interaction between the two mechanisms.
我们使用第一性原理电流转移理论计算了 BiFeO(3) 的体光伏效应(BPVE),发现与实验结果吻合较好。此外,我们还调和了明显矛盾的观察结果:通过考察所有光伏响应张量分量的贡献,并考虑实验系统的几何形状和铁电畴结构,我们解释了在带状多畴样品中明显缺乏 BPVE 响应的现象,这与在单畴样品中观察到的显著响应不一致。我们揭示了在带状多畴样品中,畴壁驱动的响应部分被 BPVE 所缓解,这表明在两种机制之间具有合作而非拮抗相互作用的材料中,可能获得更高的效率。