An organic–inorganic hybrid co-crystal complex as a high-performance solid-state nonlinear optical switch

Abstract

Solid-state nonlinear optical (NLO) switches have attracted great interest, while high performance solid-state nonlinear optical (NLO) switches still remain scarce. Herein, we firstly present a high-performance solid-state NLO switch based on an organic–inorganic hybrid co-crystal complex, [H₂dabcoCl₂][FeCl₃(H₂O)₃] (1, dabco = 1,4-diazabicyclo[2.2.2]octane). It is found that 1 exhibits a moderately large NLO response of ∼0.31 pm V⁻¹, a superior switching contrast (∼25) and a highly tunable repeatability, which may guarantee its potential device applications. In addition, microscopic crystal structural analyses reveal that its NLO switching is attributed to the order–disorder transformation of the dabco cation, cooperating with the reorientational displacement of the inorganic [FeCl₃(H₂O)₃] component. Owing to the broader designability of organic–inorganic hybrids, this work opens up an attractive approach for exploring new high-performance NLO switches.