title: Truncated spherical voids for nearly omnidirectional optical absorption.
abstract: Truncated spherical voids nanostructured tungsten films are shown to have nearly perfect absorption with characteristics of broad-band, polarization-independent and wide-incidence angle in near infrared and visible regime. Through optimizing material and structural parameters, we can achieve the absorbance above 90% from 420THz to 600THz within incidence angle from 0° to 60° for TE polarization and from 450THz to 800THz within incidence angle from 0° to 75° for TM polarization. In particular, absorbance can achieve 99.9% at 550.5THz for both polarizations under normal incidence. Such strong absorption is explained using multilayer effective media theory and cavity resonance.
authors: State Key Laboratory of Optical Technologies for Microfabrication, Institute of Optics and Electronics, Chinese Academy of Science, P.O.box 350, Chengdu 610209, China.
authors: Min
authors: M
authors: Wang
authors: Chenggang
authors: C
authors: Hu
authors: Mingbo
authors: M
authors: Pu
authors: Cheng
authors: C
authors: Huang
authors: Zeyu
authors: Z
authors: Zhao
authors: Qin
authors: Q
authors: Feng
authors: Xiangang
authors: X
authors: Luo
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D004867:Equipment Design; D008422:Materials Testing; D015233:Models, Statistical; D049329:Nanostructures / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods; D055095:Optics and Photonics; D013053:Spectrophotometry / Q000379:methods*; D013055:Spectrophotometry, Infrared / Q000379:methods