Kagome metal KV3Sb5: an excellent material for surface plasmon and plasmon-mediated hot carrier applications in the infrared region

KV3Sb5 has attracted considerable attention because of its superconductivity, which is an unconventional electronic transport property. This transport property can facilitate an excellent surface plasmon (SP) resonance effect. Herein, based on many-body first-principles methods, we studied the electronic structures and SP properties of KV3Sb5 and the generation and transport properties of plasmon-mediated hot carriers. It was concluded that the surface plasmon polariton (SPP) propagation length of KV3Sb5 can reach the centimeter-length scale in the infrared region and the localized surface plasmon resonance (LSPR) absorption efficiency and near-field enhancement are much higher for KV3Sb5 than Au. These results suggest promising SP applications of KV3Sb5 in the infrared range. In addition, the direct interband and phonon-assisted intraband electronic transitions in the SP energy range are very efficient in KV3Sb5, indicating its significant plasmon-mediated hot carrier generation ability through Landau damping. Furthermore, the mean free paths and mean free times of hot carriers were the at nanometer-length and femtosecond-time scales, respectively, which are comparable with that of Au. These results indicate the potential of KV3Sb5 for plasmon-mediated hot carrier applications.