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arXiv · 1811.05287

Shift current bulk photovoltaic effect influenced by quasiparticles and excitons

Ruixiang Fei·Liang Z. Tan·Andrew M. Rappe
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Abstract

We compute the shift current bulk photovoltaic effect (BPVE) in bulk BaTiO$_3$ and two-dimensional monochalcogenide SnSe considering quasi-particle corrections and exciton effects. We explore changes in shift current peak position and magnitude reduction due to band renormalization. For BaTiO$_3$, we demonstrate that shift current is reduced near the band edge due to exciton effects. Comparison of these results with experiments on BaTiO$_3$ indicate that mechanisms other than shift current may be contributing to BPVE. Additionally, we reveal that the shift current near the band gap shows only a small change due to excitons in two-dimensional SnSe, suggesting that the thin film geometry provides a feasible way to reduce the exciton effect on the shift current. These results suggest that many-body corrections are important for accurate assessments of bulk photovoltaic materials and to understand the mechanisms behind the BPVE

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Ruixiang Fei, Liang Z. Tan, Andrew M. Rappe. 2018-11-13. Shift current bulk photovoltaic effect influenced by quasiparticles and excitons. https://doi.org/10.1103/physrevb.101.045104

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