Site-Selective Transition-Metal Doping Enables Enhanced Nonlinear Optical Absorption in Two-Dimensional Lead-Free Double Perovskites

Ouyang C. Boukhvalov D.W. Qu Z. Humphrey M.G. Zhang C. Huang Z.
13 March 2026 John Wiley and Sons Inc

Advanced Optical Materials
2026 #14 Issue 10

Achieving high-performance nonlinear optical (NLO) absorption in lead-free perovskites remains a major challenge for advanced photonic applications. Here, we demonstrate that transition-metal doping in two-dimensional lead-free double perovskite (BA)₄AgBiBr₈—where Fe and Cu selectively substitute Bi and Ag sites, respectively—serves as an effective strategy to boost NLO responses. Structural, spectroscopic, and theoretical analyses demonstrate the site-selective doping behavior in (BA)₄AgBiBr₈ and the introduction of distinct defect states within the bandgap, which provide abundant intermediate levels for excited-state absorption under 800 nm femtosecond excitation. These defect-mediated transitions significantly amplify the NLO response, yielding over a twofold increase in the nonlinear absorption coefficient and modulation depths of ∼70–75% at ultralow pulse energy (0.7 nJ). This study establishes site-specific defect engineering as a general approach for designing high-performance, environmentally benign NLO materials.

defect , doping , double perovskite , nonlinear optical

Text of the article Перейти на текст статьи

China-Australia Joint Research Center for Functional Molecular Materials, School of Chemical Science and Engineering, Tongji University, Shanghai, China
College of Science, Nanjing Forestry University, Nanjing, China
Institute of Physics and Technology, Satbayev University, Almaty, Kazakhstan
Research School of Chemistry, Australian National University, Canberra, Australia

China-Australia Joint Research Center for Functional Molecular Materials
College of Science
Institute of Physics and Technology
Research School of Chemistry

10 лет помогаем публиковать статьи Международный издатель

Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026