论文标题
非衍射亚间隙光电流作为终生效应的探针
Nonvanishing sub-gap photocurrent as a probe of lifetime effects
论文作者
论文摘要
对于半导体和绝缘体，通常认为在缝隙内过渡到非定位状态的状态在干净极限下会平滑地抑制，即，由于状态不可用而导致的贡献消失了。我们提出了一种新型的亚间隙响应类型，该响应表明，这种直觉不会超出线性响应。也就是说，我们发现由于批量光伏效应而引起的直流电流可以是有限的，并且在允许的亚间隙跃迁窗口中大多独立于温度。我们预计中等范围的激发能位于可观察到这种效果的整体能量间隙和迁移率边缘之间。我们使用简化的松弛时间模型进行频段宽扩展，我们发现亚漏水DC汇率是非相互作用系统无关的，但对于强相互作用的系统而言，温度依赖于温度。因此，可以使用亚间隙响应来区分状态是单粒子本地化还是多体局部化。
For semiconductors and insulators, it is commonly believed that in-gap transitions into non-localized states are smoothly suppressed in the clean limit, i.e. at zero temperature their contribution vanishes due to the unavailability of states. We present a novel type of sub-gap response which shows that this intuition does not generalize beyond linear response. Namely, we find that the dc current due to the bulk photovoltaic effect can be finite and mostly temperature independent in an allowed window of sub-gap transitions. We expect that a moderate range of excitation energies lies between the bulk energy gap and the mobility edge where this effect is observable. Using a simplified relaxation time model for the band broadening, we find the sub-gap dc-current to be temperature-independent for non-interacting systems but temperature-dependent for strongly interacting systems. Thus, the sub-gap response may be used to distinguish whether a state is single-particle localized or many-body localized.
