Ultrafast Laser Pulses Induced Insulator–Metal Transition and Multiple Plasmons in Barium Titanate Quantum Dots

Abstract

Recently, all-inorganic perovskite quantum dots have become a hot research topic due to their unique optical response. We have studied barium titanate quantum dots and their hybrid structure consisting silver (Ag) nanowires interacting with ultrafast laser pulses based on time-dependent density functional theory (TDDFT). Through controlling the wavelength and intensity of incident ultrafast light pulses, insulator–metal transition and long-wavelength plasmons can be induced in barium titanate quantum dots. This is because localized field effect breaks the bonds between surrounding oxygen atoms and barium atoms, thus creating metallic patches to form photocurrents. In addition, our results elucidate that Ag nanowires can improve the ultrafast optical responsivity of barium titanate quantum dots especially in the infrared region. Our work theoretically broadens the cognition of all-inorganic perovskite quantum dots interacting with laser and reveals that inorganic perovskite quantum dots have great potential in future applications of optoelectronic devices.