title: Engineering heavily doped silicon for broadband absorber in the terahertz regime.
abstract: Highly efficient absorber is of particular importance in terahertz regime as naturally occurring materials with frequency-selective absorption in this frequency band is difficult to find. Here we present the design and characterization of a broadband terahertz absorber based on heavily Boron-doped silicon (0.7676 Ω cm) grating. It is numerically demonstrated by utilizing both the zero- and first order diffraction in the doped silicon wafer, relative absorption bandwidth larger than 100% can be achieved. Furthermore, the design can be easily extended to higher frequencies as the optical property of doped silicon is tunable through changing the doping concentration.
authors.affiliation: 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.forename: Mingbo
authors.initials: M
authors.lastname: Pu
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Chenggang
authors.initials: C
authors.lastname: Hu
authors.forename: Cheng
authors.initials: C
authors.lastname: Huang
authors.forename: Zeyu
authors.initials: Z
authors.lastname: Zhao
authors.forename: Yanqin
authors.initials: Y
authors.lastname: Wang
authors.forename: Xiangang
authors.initials: X
authors.lastname: Luo