Hot Carrier Dynamics in InAs-AlAsSb Core-Shell Nanowires

Daniel Sandner; Hamidreza Esmaielpour; Fabio del Giudice; Matthias Nuber; Reinhard Kienberger; Gregor Koblmüller; Hristo Iglev

arXiv · 2210.11886

Hot Carrier Dynamics in InAs-AlAsSb Core-Shell Nanowires

Daniel Sandner·Hamidreza Esmaielpour·Fabio del Giudice·Matthias Nuber·Reinhard Kienberger·Gregor Koblmüller·Hristo Iglev

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Abstract

Semiconductor nanowires (NWs) have shown evidence of robust hot carrier effects due to their small dimensions. The relaxation dynamics of hot carriers in these nanostructures, generated by photo-absorption, are of great importance in optoelectronic devices and high efficiency solar cells, such as hot carrier solar cells. Among various III-V semiconductors, indium arsenide (InAs) NWs are promising candidates for their applications in advanced light harvesting devices due to their high photo-absorptivity and high mobility. Here, we investigate the hot carrier dynamics in InAs-AlAsSb core-shell NWs, as well as bare-core InAs NWs, using ultrafast pump-probe spectroscopy with widely tuned pump and probe energies. We have found a lifetime of 2.3 ps for longitudinal optical (LO) phonons and hot electron lifetimes of about 3 ps and 30 ps for carrier-carrier interactions and electron-phonon interactions, respectively. In addition, we have investigated the electronic states in the AlAsSb-shell and found that, despite the large band offset of the core-shell design in the conduction band, excited carriers remain in the shell longer than 100 ps. Our results indicate evidence of plasmon-tailored core-shell NWs for efficient light harvesting devices, which could open potential avenues for improving the efficiency of photovoltaic solar cells.

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Daniel Sandner, Hamidreza Esmaielpour, Fabio del Giudice, Matthias Nuber, Reinhard Kienberger, Gregor Koblmüller, Hristo Iglev. 2022-10-21. Hot Carrier Dynamics in InAs-AlAsSb Core-Shell Nanowires. https://arxiv.org/abs/2210.11886

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