To overcome global energy challenges and fight the looming environmental crisis, researchers around the world investigate new materials for converting sunlight into electricity. Some of the most promising candidates for high-efficiency low-cost solar cell applications are based on lead halide perovskite (LHP) semiconductors. Despite record-breaking solar cell prototypes, the microscopic origin of the surprisingly excellent optoelectronic performance of this material class is still not completely understood. Now, an international team of physicists and chemists from Fritz Haber Institute of the Max Planck Society, École Polytechnique in Paris, Columbia University in New York, and the Free University in Berlin demonstrated laser-driven control of fundamental motions of the LHP atomic lattice. By applying a sudden electric field spike faster than a trillionth of a second (picosecond) in the form of a single light cycle of far-infrared Terahertz radiation, the investigators unveiled the ultrafast lattice response, which might contribute to a dynamic protection mechanism for electric charges. This precise control over the atomic twist motions will allow to create novel non-equilibrium material properties, potentially providing hints for designing the solar cell material of the future.
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