Dual-band localized surface plasmon resonance spectrum using gold nanoparticles fabricated on anisotropic crystalline 36XY-LiTaO3 substrate

Localized surface plasmon resonance is the effect when metallic nanoparticles (MeNPs) have highly interacted with incident light at a specific wavelength. Studies have focused on modifying the size, structure, and shape of MeNPs to the LSPR spectrum effect. Then, the dual-peak/dual-band LSPR spectrum was usually obtained using modify the configuration of MeNPs. However, the influences of the anisotropic crystalline substrate on the LSPR spectrum remain poorly explored. As a novelty, a dual-band LSPR using gold nanoparticles (AuNPs) was fabricated on the anisotropic crystalline 36XY-LiTaO3 substrate is proposed. Comprehensive evaluations were performed with finite-difference time-domain method (FDTD) simulation for plasmonic E-field simulation, atomic force microscopy imaging, and measurement of LSPR spectrum. As a result, the dual-band LSPR has obtained at a wavelength of 500 nm and 700 nm for the lower-band and upper band, respectively. A good agreement between simulation and measurement has validated the proposed method.