ANOMALOUS BULK PHOTO-VOLTAIC EFFECT IN FERROELECTRICS - QUADRATIC RESPONSE THEORY
ANOMALOUS BULK PHOTO-VOLTAIC EFFECT IN FERROELECTRICS - QUADRATIC RESPONSE THEORY
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DOI：
10.1103/physrevb.19.1548
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发表时间：
1979-01-01
影响因子：
3.7
通讯作者：
BALTZ, RV
中科院分区：
文献类型：
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作者：
KRAUT, W;BALTZ, RV
提出了铁电体反常光伏效应(ABPVE)中电子输运的唯象描述和量子力学理论。我们的理论是基于二次响应公式，从而得到了短路光伏电流(SCPVC)的精确表达式。这一理论表明，即使在纯Bloch态系统中也存在ABPVE。我们通过对一维独立杂质模型的SCPVC进行显式计算，证明了我们理论的能力。根据这些结果，我们得出结论：在BaTiO_3中观察到的SCPVC的符号变化要么是由于具有束缚激发态的杂质引起的，要么是由于具有两个或多个重叠的价带或导带的Bloch态引起的。这两种机制都有证据支持。
We present a phenomenological description and a quantum-mechanical theory of electron transport in the anomalous bulk photovoltaic effect (ABPVE) in ferroelectrics. Our theory is based on a quadratic response formalism which leads to an exact expression for the short-circuit photovoltaic current (SCPVC). This theory indicates the existence of an ABPVE even in a system of pure Bloch states. We demonstrate the capability of our theory by performing an explicit calculation of the SCPVC for a one-dimensional model of independent impurities. From these results we conclude that sign changes of the SCPVC, as observed in BaTi O 3, are either due to impurities which have a bound excited state, or to Bloch states with two or more overlapping valence or conduction bands. There is evidence for both mechanisms.