Title :
Multimodal Broadband Plasmonic Absorber With Densely Packed Metallic Nanostars
Author :
Hang Liu ; Kai Liu ; Lei Wang ; Suhua Jiang ; Wei Zeng
Author_Institution :
Dept. of Mater. Sci., Fudan Univ., Shanghai, China
Abstract :
A nanoplasmonic absorber consisting of a metal-dielectric-metal stack with a top layer of densely packed nanostars is designed and numerically investigated. The multimodal absorber can achieve 91% average absorption efficiency in the wavelength range of 450-700 nm. Remarkably, super absorption exhibits desirable insensitivity to both incident angles and polarization states. Electric field intensity was significantly enhanced in a nanogap region between adjacent nanostars, corresponding to an electric field enhancement factor of up to 300. Broadband absorption is attributed to the excitation of multiple resonance modes. Underlying mechanisms of individual modes were well revealed by a thorough physical analysis. The proposed absorber shows great potentials to enhance performances of various optical or optoelectronic devices.
Keywords :
dielectric materials; light absorption; light polarisation; nanophotonics; numerical analysis; optical design techniques; plasmonics; average absorption efficiency; densely packed metallic nanostar design; electric field intensity enhancement; incident angles; metal-dielectric-metal stack; multimodal broadband plasmonic absorber; multiple resonance mode excitation; nanogap region; nanoplasmonic absorber; numerical analysis; optoelectronic devices; polarization states; wavelength 450 nm to 700 nm; Absorption; Broadband communication; Electric fields; Optical filters; Optical polarization; Optical sensors; Plasmons; Broadband; nanogap; plasmonic absorber;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2015.2392552
