Dr. Usman Ali Shah is a physicist specializing in the fabrication, optimization, and characterization of thin-film photovoltaic devices, with a strong focus on emerging absorber materials such as antimony chalcogenides (Sb₂S₃, Sb₂Se₃, Sb₂(S,Se)₃), kesterites (Cu₂ZnSnS₄, Cu₂ZnSnSe₄, Cu₂ZnSn(S,Se)₄), and perovskite solar cells for both indoor and outdoor applications. Dr. Shah received his Ph.D. in Physics from the University of Florence, Italy, where his research contributed significantly to the development of high-efficiency, stable perovskite solar cells for indoor photovoltaics. With international research experience in leading laboratories across China and Europe, Dr. Shah brings a global perspective to sustainable energy research.