Single-Layer Dichroic Filters for Multifrequency Receivers at THz Frequencies

Montofre, Daniel; Khudchenko, Andrey; Mena, Fausto Patricio; Hesper, Ronald; Baryshev, Andrey M.

Abstract

In this work, we report the design, construction, and characterization of two free-standing single-layer frequency-selective surface structures to be used as dichroic filters in the THz range. Their spectral responses are aimed to fulfill a stringent band-pass performance in the atmospheric window between 600 and 725 GHz. Specifically, the dichroics have been required to allow a transmission of electromagnetic radiation of at least 90%, achieve a rejection in the stop-band lower than -25 dB, and have cross-polarization levels below -30 dB. All these specifications were demanded to be satisfied at normal and nonnormal beam incidence. We have studied dichroic filters with hexagonal patterns of two different apertures, a well-known single-hole geometry and, in order to enhance the spectral performance, a novel aperture geometry that we call the flower type. Their transmission characteristics were measured using a Fourier transform spectrometer. The electromagnetic simulations and experimental results not only show a good agreement but they demonstrate that the flower-type geometry can greatly outperform its single-hole counterpart achieving all the desired requirements. In this way, we demonstrate the feasibility of implementing single-layer systems at (sub)-THz frequencies suitable for low-noise astronomical applications.

Más información

Título según WOS: Single-Layer Dichroic Filters for Multifrequency Receivers at THz Frequencies
Título de la Revista: IEEE TRANSACTIONS ON TERAHERTZ SCIENCE AND TECHNOLOGY
Volumen: 10
Número: 6
Editorial: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Fecha de publicación: 2020
Página de inicio: 690
Página final: 697
DOI:

10.1109/TTHZ.2020.3025692

Notas: ISI