Open AccessSingle-chip source-free terahertz spectroscope across 004–099 THz: combining sub-wavelength near-field sensing and regression analysis
Author(s) -
Xue Wu,
Kaushik Sengupta
Publication year - 2018
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.007163
Subject(s) - terahertz radiation , optics , chip , amplifier , antenna (radio) , optoelectronics , spectrometer , terahertz spectroscopy and technology , materials science , wavelength , physics , computer science , telecommunications , cmos
This paper demonstrates a methodology to miniaturize THz spectroscopes into a single silicon chip by eliminating traditional solid-state architectural components such as complex tunable THz and optical sources, nonlinear mixing and amplifiers. The proposed method achieves this by extracting incident THz spectral signatures from the surface of an on-chip antenna itself. The information is sensed through the spectrally-sensitive 2D distribution of the impressed current surface under the THz incident field. By converting the antenna from a single-port to a massively multi-port architecture with integrated electronics and deep subwavelength sensing, THz spectral estimation is converted into a linear estimation problem. We employ rigorous regression techniques and analysis to demonstrate a single silicon chip system operating at room temperature across 0.04-0.99 THz with 10 MHz accuracy in spectrum estimation of THz tones across the entire spectrum.