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arXiv · 2507.13279

Improving photovoltaics by adding extra terminals to extract hot carriers

Bruno Bertin-Johannet·Thibaut Thuégaz·Janine Splettstoesser·Robert S. Whitney
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Abstract

Photovoltaic cells usually have two terminals, one collecting electrons and the other collecting holes. Can more terminals improve such solar cells? Energy-filtering terminals could collect "hot" carriers (electrons or holes not yet relaxed to the band edge), with other terminals for low-energy carriers. When collection is faster than carrier-phonon relaxation, we predict that four-terminal cells have higher power output than optimal two-terminal cells, often 20-40% higher. Similar effects will occur in multi-terminal thermoelectrics exploiting non-equilibrium distributions.

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Bruno Bertin-Johannet, Thibaut Thuégaz, Janine Splettstoesser, Robert S. Whitney. 2025-07-17. Improving photovoltaics by adding extra terminals to extract hot carriers. https://arxiv.org/abs/2507.13279

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