Infrared (IR) photodetection based on two-dimensional (2D) materials has attracted increasing attention. However, the ultrathin property and indirect bandgap in few-layer structures significantly degrade the IR photodetection performance. In this work, based on few-layer MoTe2 that with a proper bandgap at IR regime, we have demonstrated a remarkable IR photodetection response enhancement with a ~ 60 times by introducing a novel gold hollow nanorods (AuHNRs) on the surface. The localized surface plasmon resonance (LSPR) induced by metal nanoparticles is an effective strategy to enhance light absorption. This AuHNRs has a strong plasmon band located at the IR regime, breaking the limitation of resonance range at visible. Both the steady and transient optical spectra give evidence...[ Read more ]

Infrared (IR) photodetection based on two-dimensional (2D) materials has attracted increasing attention. However, the ultrathin property and indirect bandgap in few-layer structures significantly degrade the IR photodetection performance. In this work, based on few-layer MoTe2 that with a proper bandgap at IR regime, we have demonstrated a remarkable IR photodetection response enhancement with a ~ 60 times by introducing a novel gold hollow nanorods (AuHNRs) on the surface. The localized surface plasmon resonance (LSPR) induced by metal nanoparticles is an effective strategy to enhance light absorption. This AuHNRs has a strong plasmon band located at the IR regime, breaking the limitation of resonance range at visible. Both the steady and transient optical spectra give evidence to confirm that the enhancement of IR response concerning photon absorption correlates with the plasmon-induced field enhancement, rather than hot charge transport between metal and semiconductor. Therefore, this strategy can dispense with the strict restriction of interface quality and offers significant advantages in large scale application compared to other methods.