Unearthing Superior Inorganic UV Second-Order Nonlinear Optical Materials: A Mineral-Inspired Method Integrating First-Principles High-Throughput Screening and Crystal Engineering.

Abstract

Natural minerals, with their adaptable framework structures exemplified by perovskite and lyonsite, have sparked substantial interest as potential templates for the design of advanced functional solid-state materials. Nonetheless, the quest for new materials with desired properties remains a substantial challenge, primarily due to the scarcity of effective and practical synthetic approaches. In this study, we have harnessed a synergistic approach that seamlessly integrates first-principles high-throughput screening and crystal engineering to reinvigorate the often-overlooked fresnoite mineral, Ba2 TiOSi2 O7 . This innovative strategy has culminated in the successful synthesis of two superior inorganic UV nonlinear optical materials, namely Rb2 TeOP2 O7 and Rb2 SbFP2 O7 . Notably, Rb2 SbFP2 O7 demonstrates a comprehensive enhancement in nonlinear optical performance, featuring a shortened UV absorption edge (260 nm) and a more robust second-harmonic generation response (5.1×KDP). Particularly striking is its significantly increased birefringence (0.15@546 nm), which is approximately 30 times higher than the prototype Ba2 TiOSi2 O7 (0.005@546 nm). Our research has not only revitalized the potential of the fresnoite mineral for the development of new high-performance UV nonlinear optical materials but has also provided a clearly defined roadmap for the efficient exploration of novel structure-driven functional materials with targeted properties.