Open AccessCoherent imaging using laser feedback interferometry with pulsed-mode terahertz quantum cascade lasers
Author(s) -
Yah Leng Lim,
Karl Bertling,
Thomas Taimre,
Tim Gillespie,
Chris Glenn,
Ashley Robinson,
D. Indjin,
Yazhou Han,
Lianhe Li,
Edmund H. Linfield,
A. G. Davies,
Paul Dean,
Aleksandar D. Rakić
Publication year - 2019
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.27.010221
Subject(s) - optics , terahertz radiation , laser , interferometry , cascade , quantum cascade laser , far infrared laser , photomixing , optoelectronics , terahertz spectroscopy and technology , physics , materials science , terahertz metamaterials , chemistry , chromatography
We report a coherent terahertz (THz) imaging system that utilises a quantum cascade laser (QCL) operating in pulsed-mode as both the source and detector. The realisation of a short-pulsed THz QCL feedback interferometer permits both high peak powers and improved thermal efficiency, which enables the cryogen-free operation of the system. In this work, we demonstrated pulsed-mode swept-frequency laser feedback interferometry experimentally. Our interferometric detection scheme not only permits the simultaneous creation of both amplitude and phase images, but inherently suppresses unwanted background radiation. We demonstrate that the proposed system utilising microsecond pulses has the potential to achieve 0.25 mega-pixel per second acquisition rates, paving the pathway to video frame rate THz imaging.