标题： 铁电材料中固有反带隙与极化的关系 显示英文标题

标题： Intrinsic inverse band gap versus polarization relation in ferroelectric materials

摘要： 铁电材料在太阳能转换和电光器件中具有广阔的应用前景。 由宏观极化产生的内部梯度场可能改善电子和传输半导体特性。 然而，铁电材料往往表现出相对较大的带隙，因此太阳能转换效率较低。 在本研究中，我们探索了单个铁电相中带隙与极化之间存在内在反比关系的材料。 具有反向带隙与极化关系的铁电材料的特点是在导带状态处的态密度贡献较低，且在价带状态处的轨道杂化可以忽略不计。 我们使用高通量和第一性原理方法在Materials Project数据库中找到15种具有反向带隙与极化关系的铁电材料。 我们的工作提供了一种新的设计小带隙大极化铁电材料的途径，通过外部调节参数同时调节具有反向关系的铁电材料的带隙和极化。 显示英文摘要

摘要： Ferroelectric materials have promising applications in solar-energy conversion and electro-optic devices. The internal gradient fields produced by the macroscopic polarization may improve electronic and transport semiconducting properties. However, ferroelectrics tend to display relatively large band gaps and hence low solar-energy conversion efficiencies. In this work, we explore materials with an intrinsic inverse relation between band gap and polarization in a single ferroelectric phase. Ferroelectrics with an inverse band gap versus polarization relation are characterized by low density of states contribution at the conduction states and negligible orbital hybridization at the valence states. We use high-throughput and first principles methods to find 15 ferroelectric materials with an inverse band gap versus polarization relation in the Materials Project database. Our work provides a new pathway to design small-band gap large-polarization ferroelectrics, by simultaneously tailoring the band gap and polarization of ferroelectrics with an inverse relation through an external tuning parameter.