Anna Fontcuberta i Morral
École Polytechnique Fédérale de Lausanne
New Materials and Structures for Photodetection
Some compound semiconductors such as GaAs and InGaAsP exhibit a high absorption coefficient in the photon energy of interest for solar energy conversion. The direct bandgap associated with strong tuneability of emission wavelength, renders compound semiocnductors the material of choice for optoelectronic applications. Their commercial potential in high production volume applications is reduced due to the scarcity (and thus high cost) of group III elements such as In and Ga. In this talk we present approaches to render the use this kind of materials sustainable: a strong reduction in material use through nanostructures and the replacement of III-V compounds by GeSn or Zn3P2 that contain much more abundant elements. We find nanostructures also provide a path to increase light collection and provide some instructions for optimal devices[1,2]. We explain how these materials can be fabricated with high crystal quality, opening the path for the creation of alternative and sustainable compound semiconductor solar cells [3-5].
 P. Krogstrup et al Nature Photon 7, 306 (2013)
 A. Dorodnyy et al IEEE Journal of Selected Topics in Quantum Electronics 24, 1-13 (2018)
 S. Escobar Steinvall et al Nanoscale Horizons 5, 274-282 (2020)
 R. Paul et al, Crys. Growth. Des. 20, 3816–3825 (2020)
 S. Escobar Steinval et al. Nanoscale Adv. 3, 326 (2021)
About the Speaker
Anna Fontcuberta i Morral is Spanish physicist and materials scientist. Her research focuses on nanotechnology applied in the production of solar cells. She is a Full Professor at École Polytechnique Fédérale de Lausanne and the head of the Laboratory of Semiconductor Materials.