Journal article
Ji-Hee Kim, Matthew R. Bergren, Jin Cheol Park, S. Adhikari, M. Lorke, T. Fraunheim, D. Choe, B. Kim, Hyunyong Choi, T. Gregorkiewicz, Young Hee Lee
2018
2018
Semantic Scholar
ArXiv
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APA
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Kim, J.-H., Bergren, M. R., Park, J. C., Adhikari, S., Lorke, M., Fraunheim, T., … Lee, Y. H. (2018). Highly Efficient Carrier Multiplication in van der Waals layered Materials.
Chicago/Turabian
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Kim, Ji-Hee, Matthew R. Bergren, Jin Cheol Park, S. Adhikari, M. Lorke, T. Fraunheim, D. Choe, et al. “Highly Efficient Carrier Multiplication in Van Der Waals Layered Materials” (2018).
MLA
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Kim, Ji-Hee, et al. Highly Efficient Carrier Multiplication in Van Der Waals Layered Materials. 2018.
BibTeX Click to copy
@article{ji-hee2018a,
title = {Highly Efficient Carrier Multiplication in van der Waals layered Materials},
year = {2018},
author = {Kim, Ji-Hee and Bergren, Matthew R. and Park, Jin Cheol and Adhikari, S. and Lorke, M. and Fraunheim, T. and Choe, D. and Kim, B. and Choi, Hyunyong and Gregorkiewicz, T. and Lee, Young Hee}
}
Abstract
Carrier multiplication (CM), a photo-physical process to generate multiple electron-hole pairs by exploiting excess energy of free carriers, is explored for efficient photovoltaic conversion of photons from the blue solar band, predominantly wasted as heat in standard solar cells. Current state-of-the-art approaches with nanomaterials have demonstrated improved CM but are not satisfactory due to high energy loss and inherent difficulties with carrier extraction. Here, we report ultra-efficient CM in van der Waals (vdW) layered materials that commences at the energy conservation limit and proceeds with nearly 100% conversion efficiency. A small threshold energy, as low as twice the bandgap, was achieved, marking an onset of quantum yield with enhanced carrier generation. Strong Coulomb interactions between electrons confined within vdW layers allow rapid electron-electron scattering to prevail over electron-phonon scattering. Additionally, the presence of electron pockets spread over momentum space could also contribute to the high CM efficiency. Combining with high conductivity and optimal bandgap, these superior CM characteristics identify vdW materials for third-generation solar cell.
